mumble

mpc.c (111471B)

---

 #include "mpc.h"
 
 /*
 ** State Type
 */
 
 static mpc_state_t mpc_state_invalid(void) {
   mpc_state_t s;
   s.pos = -1;
   s.row = -1;
   s.col = -1;
   s.term = 0;
   return s;
 }
 
 static mpc_state_t mpc_state_new(void) {
   mpc_state_t s;
   s.pos = 0;
   s.row = 0;
   s.col = 0;
   s.term = 0;
   return s;
 }
 
 /*
 ** Input Type
 */
 
 /*
 ** In mpc the input type has three modes of
 ** operation: String, File and Pipe.
 **
 ** String is easy. The whole contents are
 ** loaded into a buffer and scanned through.
 ** The cursor can jump around at will making
 ** backtracking easy.
 **
 ** The second is a File which is also somewhat
 ** easy. The contents are never loaded into
 ** memory but backtracking can still be achieved
 ** by seeking in the file at different positions.
 **
 ** The final mode is Pipe. This is the difficult
 ** one. As we assume pipes cannot be seeked - and
 ** only support a single character lookahead at
 ** any point, when the input is marked for a
 ** potential backtracking we start buffering any
 ** input.
 **
 ** This means that if we are requested to seek
 ** back we can simply start reading from the
 ** buffer instead of the input.
 **
 ** Of course using `mpc_predictive` will disable
 ** backtracking and make LL(1) grammars easy
 ** to parse for all input methods.
 **
 */
 
 enum {
   MPC_INPUT_STRING = 0,
   MPC_INPUT_FILE   = 1,
   MPC_INPUT_PIPE   = 2
 };
 
 enum {
   MPC_INPUT_MARKS_MIN = 32
 };
 
 enum {
   MPC_INPUT_MEM_NUM = 512
 };
 
 typedef struct {
   char mem[64];
 } mpc_mem_t;
 
 typedef struct {
 
   int type;
   char *filename;
   mpc_state_t state;
 
   char *string;
   char *buffer;
   FILE *file;
 
   int suppress;
   int backtrack;
   int marks_slots;
   int marks_num;
   mpc_state_t *marks;
 
   char *lasts;
   char last;
 
   size_t mem_index;
   char mem_full[MPC_INPUT_MEM_NUM];
   mpc_mem_t mem[MPC_INPUT_MEM_NUM];
 
 } mpc_input_t;
 
 static mpc_input_t *mpc_input_new_string(const char *filename, const char *string) {
 
   mpc_input_t *i = malloc(sizeof(mpc_input_t));
 
   i->filename = malloc(strlen(filename) + 1);
   strcpy(i->filename, filename);
   i->type = MPC_INPUT_STRING;
 
   i->state = mpc_state_new();
 
   i->string = malloc(strlen(string) + 1);
   strcpy(i->string, string);
   i->buffer = NULL;
   i->file = NULL;
 
   i->suppress = 0;
   i->backtrack = 1;
   i->marks_num = 0;
   i->marks_slots = MPC_INPUT_MARKS_MIN;
   i->marks = malloc(sizeof(mpc_state_t) * i->marks_slots);
   i->lasts = malloc(sizeof(char) * i->marks_slots);
   i->last = '\0';
 
   i->mem_index = 0;
   memset(i->mem_full, 0, sizeof(char) * MPC_INPUT_MEM_NUM);
 
   return i;
 }
 
 static mpc_input_t *mpc_input_new_nstring(const char *filename, const char *string, size_t length) {
 
   mpc_input_t *i = malloc(sizeof(mpc_input_t));
 
   i->filename = malloc(strlen(filename) + 1);
   strcpy(i->filename, filename);
   i->type = MPC_INPUT_STRING;
 
   i->state = mpc_state_new();
 
   i->string = malloc(length + 1);
   strncpy(i->string, string, length);
   i->string[length] = '\0';
   i->buffer = NULL;
   i->file = NULL;
 
   i->suppress = 0;
   i->backtrack = 1;
   i->marks_num = 0;
   i->marks_slots = MPC_INPUT_MARKS_MIN;
   i->marks = malloc(sizeof(mpc_state_t) * i->marks_slots);
   i->lasts = malloc(sizeof(char) * i->marks_slots);
   i->last = '\0';
 
   i->mem_index = 0;
   memset(i->mem_full, 0, sizeof(char) * MPC_INPUT_MEM_NUM);
 
   return i;
 
 }
 
 static mpc_input_t *mpc_input_new_pipe(const char *filename, FILE *pipe) {
 
   mpc_input_t *i = malloc(sizeof(mpc_input_t));
 
   i->filename = malloc(strlen(filename) + 1);
   strcpy(i->filename, filename);
 
   i->type = MPC_INPUT_PIPE;
   i->state = mpc_state_new();
 
   i->string = NULL;
   i->buffer = NULL;
   i->file = pipe;
 
   i->suppress = 0;
   i->backtrack = 1;
   i->marks_num = 0;
   i->marks_slots = MPC_INPUT_MARKS_MIN;
   i->marks = malloc(sizeof(mpc_state_t) * i->marks_slots);
   i->lasts = malloc(sizeof(char) * i->marks_slots);
   i->last = '\0';
 
   i->mem_index = 0;
   memset(i->mem_full, 0, sizeof(char) * MPC_INPUT_MEM_NUM);
 
   return i;
 
 }
 
 static mpc_input_t *mpc_input_new_file(const char *filename, FILE *file) {
 
   mpc_input_t *i = malloc(sizeof(mpc_input_t));
 
   i->filename = malloc(strlen(filename) + 1);
   strcpy(i->filename, filename);
   i->type = MPC_INPUT_FILE;
   i->state = mpc_state_new();
 
   i->string = NULL;
   i->buffer = NULL;
   i->file = file;
 
   i->suppress = 0;
   i->backtrack = 1;
   i->marks_num = 0;
   i->marks_slots = MPC_INPUT_MARKS_MIN;
   i->marks = malloc(sizeof(mpc_state_t) * i->marks_slots);
   i->lasts = malloc(sizeof(char) * i->marks_slots);
   i->last = '\0';
 
   i->mem_index = 0;
   memset(i->mem_full, 0, sizeof(char) * MPC_INPUT_MEM_NUM);
 
   return i;
 }
 
 static void mpc_input_delete(mpc_input_t *i) {
 
   free(i->filename);
 
   if (i->type == MPC_INPUT_STRING) { free(i->string); }
   if (i->type == MPC_INPUT_PIPE) { free(i->buffer); }
 
   free(i->marks);
   free(i->lasts);
   free(i);
 }
 
 static int mpc_mem_ptr(mpc_input_t *i, void *p) {
   return
     (char*)p >= (char*)(i->mem) &&
     (char*)p <  (char*)(i->mem) + (MPC_INPUT_MEM_NUM * sizeof(mpc_mem_t));
 }
 
 static void *mpc_malloc(mpc_input_t *i, size_t n) {
   size_t j;
   char *p;
 
   if (n > sizeof(mpc_mem_t)) { return malloc(n); }
 
   j = i->mem_index;
   do {
     if (!i->mem_full[i->mem_index]) {
       p = (void*)(i->mem + i->mem_index);
       i->mem_full[i->mem_index] = 1;
       i->mem_index = (i->mem_index+1) % MPC_INPUT_MEM_NUM;
       return p;
     }
     i->mem_index = (i->mem_index+1) % MPC_INPUT_MEM_NUM;
   } while (j != i->mem_index);
 
   return malloc(n);
 }
 
 static void *mpc_calloc(mpc_input_t *i, size_t n, size_t m) {
   char *x = mpc_malloc(i, n * m);
   memset(x, 0, n * m);
   return x;
 }
 
 static void mpc_free(mpc_input_t *i, void *p) {
   size_t j;
   if (!mpc_mem_ptr(i, p)) { free(p); return; }
   j = ((size_t)(((char*)p) - ((char*)i->mem))) / sizeof(mpc_mem_t);
   i->mem_full[j] = 0;
 }
 
 static void *mpc_realloc(mpc_input_t *i, void *p, size_t n) {
 
   char *q = NULL;
 
   if (!mpc_mem_ptr(i, p)) { return realloc(p, n); }
 
   if (n > sizeof(mpc_mem_t)) {
     q = malloc(n);
     memcpy(q, p, sizeof(mpc_mem_t));
     mpc_free(i, p);
     return q;
   }
 
   return p;
 }
 
 static void *mpc_export(mpc_input_t *i, void *p) {
   char *q = NULL;
   if (!mpc_mem_ptr(i, p)) { return p; }
   q = malloc(sizeof(mpc_mem_t));
   memcpy(q, p, sizeof(mpc_mem_t));
   mpc_free(i, p);
   return q;
 }
 
 static void mpc_input_backtrack_disable(mpc_input_t *i) { i->backtrack--; }
 static void mpc_input_backtrack_enable(mpc_input_t *i) { i->backtrack++; }
 
 static void mpc_input_suppress_disable(mpc_input_t *i) { i->suppress--; }
 static void mpc_input_suppress_enable(mpc_input_t *i) { i->suppress++; }
 
 static void mpc_input_mark(mpc_input_t *i) {
 
   if (i->backtrack < 1) { return; }
 
   i->marks_num++;
 
   if (i->marks_num > i->marks_slots) {
     i->marks_slots = i->marks_num + i->marks_num / 2;
     i->marks = realloc(i->marks, sizeof(mpc_state_t) * i->marks_slots);
     i->lasts = realloc(i->lasts, sizeof(char) * i->marks_slots);
   }
 
   i->marks[i->marks_num-1] = i->state;
   i->lasts[i->marks_num-1] = i->last;
 
   if (i->type == MPC_INPUT_PIPE && i->marks_num == 1) {
     i->buffer = calloc(1, 1);
   }
 
 }
 
 static void mpc_input_unmark(mpc_input_t *i) {
   int j;
 
   if (i->backtrack < 1) { return; }
 
   i->marks_num--;
 
   if (i->marks_slots > i->marks_num + i->marks_num / 2
   &&  i->marks_slots > MPC_INPUT_MARKS_MIN) {
     i->marks_slots =
       i->marks_num > MPC_INPUT_MARKS_MIN ?
       i->marks_num : MPC_INPUT_MARKS_MIN;
     i->marks = realloc(i->marks, sizeof(mpc_state_t) * i->marks_slots);
     i->lasts = realloc(i->lasts, sizeof(char) * i->marks_slots);
   }
 
   if (i->type == MPC_INPUT_PIPE && i->marks_num == 0) {
     for (j = strlen(i->buffer) - 1; j >= 0; j--)
       ungetc(i->buffer[j], i->file);
 
     free(i->buffer);
     i->buffer = NULL;
   }
 
 }
 
 static void mpc_input_rewind(mpc_input_t *i) {
 
   if (i->backtrack < 1) { return; }
 
   i->state = i->marks[i->marks_num-1];
   i->last  = i->lasts[i->marks_num-1];
 
   if (i->type == MPC_INPUT_FILE) {
     fseek(i->file, i->state.pos, SEEK_SET);
   }
 
   mpc_input_unmark(i);
 }
 
 static int mpc_input_buffer_in_range(mpc_input_t *i) {
   return i->state.pos < (long)(strlen(i->buffer) + i->marks[0].pos);
 }
 
 static char mpc_input_buffer_get(mpc_input_t *i) {
   return i->buffer[i->state.pos - i->marks[0].pos];
 }
 
 static char mpc_input_getc(mpc_input_t *i) {
 
   char c = '\0';
 
   switch (i->type) {
 
     case MPC_INPUT_STRING: return i->string[i->state.pos];
     case MPC_INPUT_FILE: c = fgetc(i->file); return c;
     case MPC_INPUT_PIPE:
 
       if (!i->buffer) { c = getc(i->file); return c; }
 
       if (i->buffer && mpc_input_buffer_in_range(i)) {
         c = mpc_input_buffer_get(i);
         return c;
       } else {
         c = getc(i->file);
         return c;
       }
 
     default: return c;
   }
 }
 
 static char mpc_input_peekc(mpc_input_t *i) {
 
   char c = '\0';
 
   switch (i->type) {
     case MPC_INPUT_STRING: return i->string[i->state.pos];
     case MPC_INPUT_FILE:
 
       c = fgetc(i->file);
       if (feof(i->file)) { return '\0'; }
 
       fseek(i->file, -1, SEEK_CUR);
       return c;
 
     case MPC_INPUT_PIPE:
 
       if (!i->buffer) {
         c = getc(i->file);
         if (feof(i->file)) { return '\0'; }
         ungetc(c, i->file);
         return c;
       }
 
       if (i->buffer && mpc_input_buffer_in_range(i)) {
         return mpc_input_buffer_get(i);
       } else {
         c = getc(i->file);
         if (feof(i->file)) { return '\0'; }
         ungetc(c, i->file);
         return c;
       }
 
     default: return c;
   }
 
 }
 
 static int mpc_input_terminated(mpc_input_t *i) {
   return mpc_input_peekc(i) == '\0';
 }
 
 static int mpc_input_failure(mpc_input_t *i, char c) {
 
   switch (i->type) {
     case MPC_INPUT_STRING: { break; }
     case MPC_INPUT_FILE: fseek(i->file, -1, SEEK_CUR); { break; }
     case MPC_INPUT_PIPE: {
 
       if (!i->buffer) { ungetc(c, i->file); break; }
 
       if (i->buffer && mpc_input_buffer_in_range(i)) {
         break;
       } else {
         ungetc(c, i->file);
       }
     }
     default: { break; }
   }
   return 0;
 }
 
 static int mpc_input_success(mpc_input_t *i, char c, char **o) {
 
   if (i->type == MPC_INPUT_PIPE
   &&  i->buffer && !mpc_input_buffer_in_range(i)) {
     i->buffer = realloc(i->buffer, strlen(i->buffer) + 2);
     i->buffer[strlen(i->buffer) + 1] = '\0';
     i->buffer[strlen(i->buffer) + 0] = c;
   }
 
   i->last = c;
   i->state.pos++;
   i->state.col++;
 
   if (c == '\n') {
     i->state.col = 0;
     i->state.row++;
   }
 
   if (o) {
     (*o) = mpc_malloc(i, 2);
     (*o)[0] = c;
     (*o)[1] = '\0';
   }
 
   return 1;
 }
 
 static int mpc_input_any(mpc_input_t *i, char **o) {
   char x;
   if (mpc_input_terminated(i)) { return 0; }
   x = mpc_input_getc(i);
   return mpc_input_success(i, x, o);
 }
 
 static int mpc_input_char(mpc_input_t *i, char c, char **o) {
   char x;
   if (mpc_input_terminated(i)) { return 0; }
   x = mpc_input_getc(i);
   return x == c ? mpc_input_success(i, x, o) : mpc_input_failure(i, x);
 }
 
 static int mpc_input_range(mpc_input_t *i, char c, char d, char **o) {
   char x;
   if (mpc_input_terminated(i)) { return 0; }
   x = mpc_input_getc(i);
   return x >= c && x <= d ? mpc_input_success(i, x, o) : mpc_input_failure(i, x);
 }
 
 static int mpc_input_oneof(mpc_input_t *i, const char *c, char **o) {
   char x;
   if (mpc_input_terminated(i)) { return 0; }
   x = mpc_input_getc(i);
   return strchr(c, x) != 0 ? mpc_input_success(i, x, o) : mpc_input_failure(i, x);
 }
 
 static int mpc_input_noneof(mpc_input_t *i, const char *c, char **o) {
   char x;
   if (mpc_input_terminated(i)) { return 0; }
   x = mpc_input_getc(i);
   return strchr(c, x) == 0 ? mpc_input_success(i, x, o) : mpc_input_failure(i, x);
 }
 
 static int mpc_input_satisfy(mpc_input_t *i, int(*cond)(char), char **o) {
   char x;
   if (mpc_input_terminated(i)) { return 0; }
   x = mpc_input_getc(i);
   return cond(x) ? mpc_input_success(i, x, o) : mpc_input_failure(i, x);
 }
 
 static int mpc_input_string(mpc_input_t *i, const char *c, char **o) {
 
   const char *x = c;
 
   mpc_input_mark(i);
   while (*x) {
     if (!mpc_input_char(i, *x, NULL)) {
       mpc_input_rewind(i);
       return 0;
     }
     x++;
   }
   mpc_input_unmark(i);
 
   *o = mpc_malloc(i, strlen(c) + 1);
   strcpy(*o, c);
   return 1;
 }
 
 static int mpc_input_anchor(mpc_input_t* i, int(*f)(char,char), char **o) {
   *o = NULL;
   return f(i->last, mpc_input_peekc(i));
 }
 
 static int mpc_input_soi(mpc_input_t* i, char **o) {
   *o = NULL;
   return i->last == '\0';
 }
 
 static int mpc_input_eoi(mpc_input_t* i, char **o) {
   *o = NULL;
   if (i->state.term) {
     return 0;
   } else if (mpc_input_terminated(i)) {
     i->state.term = 1;
     return 1;
   } else {
     return 0;
   }
 }
 
 static mpc_state_t *mpc_input_state_copy(mpc_input_t *i) {
   mpc_state_t *r = mpc_malloc(i, sizeof(mpc_state_t));
   memcpy(r, &i->state, sizeof(mpc_state_t));
   return r;
 }
 
 /*
 ** Error Type
 */
 
 void mpc_err_delete(mpc_err_t *x) {
   int i;
   for (i = 0; i < x->expected_num; i++) { free(x->expected[i]); }
   free(x->expected);
   free(x->filename);
   free(x->failure);
   free(x);
 }
 
 void mpc_err_print(mpc_err_t *x) {
   mpc_err_print_to(x, stdout);
 }
 
 void mpc_err_print_to(mpc_err_t *x, FILE *f) {
   char *str = mpc_err_string(x);
   fprintf(f, "%s", str);
   free(str);
 }
 
 static void mpc_err_string_cat(char *buffer, int *pos, int *max, char const *fmt, ...) {
   /* TODO: Error Checking on Length */
   int left = ((*max) - (*pos));
   va_list va;
   va_start(va, fmt);
   if (left < 0) { left = 0;}
   (*pos) += vsprintf(buffer + (*pos), fmt, va);
   va_end(va);
 }
 
 static const char *mpc_err_char_unescape(char c, char char_unescape_buffer[4]) {
 
   char_unescape_buffer[0] = '\'';
   char_unescape_buffer[1] = ' ';
   char_unescape_buffer[2] = '\'';
   char_unescape_buffer[3] = '\0';
 
   switch (c) {
     case '\a': return "bell";
     case '\b': return "backspace";
     case '\f': return "formfeed";
     case '\r': return "carriage return";
     case '\v': return "vertical tab";
     case '\0': return "end of input";
     case '\n': return "newline";
     case '\t': return "tab";
     case ' ' : return "space";
     default:
       char_unescape_buffer[1] = c;
       return char_unescape_buffer;
   }
 
 }
 
 char *mpc_err_string(mpc_err_t *x) {
 
   int i;
   int pos = 0;
   int max = 1023;
   char *buffer = calloc(1, 1024);
   char char_unescape_buffer[4];
 
   if (x->failure) {
     mpc_err_string_cat(buffer, &pos, &max,
     "%s: error: %s\n", x->filename, x->failure);
     return buffer;
   }
 
   mpc_err_string_cat(buffer, &pos, &max,
     "%s:%li:%li: error: expected ", x->filename, x->state.row+1, x->state.col+1);
 
   if (x->expected_num == 0) { mpc_err_string_cat(buffer, &pos, &max, "ERROR: NOTHING EXPECTED"); }
   if (x->expected_num == 1) { mpc_err_string_cat(buffer, &pos, &max, "%s", x->expected[0]); }
   if (x->expected_num >= 2) {
 
     for (i = 0; i < x->expected_num-2; i++) {
       mpc_err_string_cat(buffer, &pos, &max, "%s, ", x->expected[i]);
     }
 
     mpc_err_string_cat(buffer, &pos, &max, "%s or %s",
       x->expected[x->expected_num-2],
       x->expected[x->expected_num-1]);
   }
 
   mpc_err_string_cat(buffer, &pos, &max, " at ");
   mpc_err_string_cat(buffer, &pos, &max, mpc_err_char_unescape(x->received, char_unescape_buffer));
   mpc_err_string_cat(buffer, &pos, &max, "\n");
 
   return realloc(buffer, strlen(buffer) + 1);
 }
 
 static mpc_err_t *mpc_err_new(mpc_input_t *i, const char *expected) {
   mpc_err_t *x;
   if (i->suppress) { return NULL; }
   x = mpc_malloc(i, sizeof(mpc_err_t));
   x->filename = mpc_malloc(i, strlen(i->filename) + 1);
   strcpy(x->filename, i->filename);
   x->state = i->state;
   x->expected_num = 1;
   x->expected = mpc_malloc(i, sizeof(char*));
   x->expected[0] = mpc_malloc(i, strlen(expected) + 1);
   strcpy(x->expected[0], expected);
   x->failure = NULL;
   x->received = mpc_input_peekc(i);
   return x;
 }
 
 static mpc_err_t *mpc_err_fail(mpc_input_t *i, const char *failure) {
   mpc_err_t *x;
   if (i->suppress) { return NULL; }
   x = mpc_malloc(i, sizeof(mpc_err_t));
   x->filename = mpc_malloc(i, strlen(i->filename) + 1);
   strcpy(x->filename, i->filename);
   x->state = i->state;
   x->expected_num = 0;
   x->expected = NULL;
   x->failure = mpc_malloc(i, strlen(failure) + 1);
   strcpy(x->failure, failure);
   x->received = ' ';
   return x;
 }
 
 static mpc_err_t *mpc_err_file(const char *filename, const char *failure) {
   mpc_err_t *x;
   x = malloc(sizeof(mpc_err_t));
   x->filename = malloc(strlen(filename) + 1);
   strcpy(x->filename, filename);
   x->state = mpc_state_new();
   x->expected_num = 0;
   x->expected = NULL;
   x->failure = malloc(strlen(failure) + 1);
   strcpy(x->failure, failure);
   x->received = ' ';
   return x;
 }
 
 static void mpc_err_delete_internal(mpc_input_t *i, mpc_err_t *x) {
   int j;
   if (x == NULL) { return; }
   for (j = 0; j < x->expected_num; j++) { mpc_free(i, x->expected[j]); }
   mpc_free(i, x->expected);
   mpc_free(i, x->filename);
   mpc_free(i, x->failure);
   mpc_free(i, x);
 }
 
 static mpc_err_t *mpc_err_export(mpc_input_t *i, mpc_err_t *x) {
   int j;
   for (j = 0; j < x->expected_num; j++) {
     x->expected[j] = mpc_export(i, x->expected[j]);
   }
   x->expected = mpc_export(i, x->expected);
   x->filename = mpc_export(i, x->filename);
   x->failure = mpc_export(i, x->failure);
   return mpc_export(i, x);
 }
 
 static int mpc_err_contains_expected(mpc_input_t *i, mpc_err_t *x, char *expected) {
   int j;
   (void)i;
   for (j = 0; j < x->expected_num; j++) {
     if (strcmp(x->expected[j], expected) == 0) { return 1; }
   }
   return 0;
 }
 
 static void mpc_err_add_expected(mpc_input_t *i, mpc_err_t *x, char *expected) {
   (void)i;
   x->expected_num++;
   x->expected = mpc_realloc(i, x->expected, sizeof(char*) * x->expected_num);
   x->expected[x->expected_num-1] = mpc_malloc(i, strlen(expected) + 1);
   strcpy(x->expected[x->expected_num-1], expected);
 }
 
 static mpc_err_t *mpc_err_or(mpc_input_t *i, mpc_err_t** x, int n) {
 
   int j, k, fst;
   mpc_err_t *e;
 
   fst = -1;
   for (j = 0; j < n; j++) {
     if (x[j] != NULL) { fst = j; }
   }
 
   if (fst == -1) { return NULL; }
 
   e = mpc_malloc(i, sizeof(mpc_err_t));
   e->state = mpc_state_invalid();
   e->expected_num = 0;
   e->expected = NULL;
   e->failure = NULL;
   e->filename = mpc_malloc(i, strlen(x[fst]->filename)+1);
   strcpy(e->filename, x[fst]->filename);
 
   for (j = 0; j < n; j++) {
     if (x[j] == NULL) { continue; }
     if (x[j]->state.pos > e->state.pos) { e->state = x[j]->state; }
   }
 
   for (j = 0; j < n; j++) {
     if (x[j] == NULL) { continue; }
     if (x[j]->state.pos < e->state.pos) { continue; }
 
     if (x[j]->failure) {
       e->failure = mpc_malloc(i, strlen(x[j]->failure)+1);
       strcpy(e->failure, x[j]->failure);
       break;
     }
 
     e->received = x[j]->received;
 
     for (k = 0; k < x[j]->expected_num; k++) {
       if (!mpc_err_contains_expected(i, e, x[j]->expected[k])) {
         mpc_err_add_expected(i, e, x[j]->expected[k]);
       }
     }
   }
 
   for (j = 0; j < n; j++) {
     if (x[j] == NULL) { continue; }
     mpc_err_delete_internal(i, x[j]);
   }
 
   return e;
 }
 
 static mpc_err_t *mpc_err_repeat(mpc_input_t *i, mpc_err_t *x, const char *prefix) {
 
   int j = 0;
   size_t l = 0;
   char *expect = NULL;
 
   if (x == NULL) { return NULL; }
 
   if (x->expected_num == 0) {
     expect = mpc_calloc(i, 1, 1);
     x->expected_num = 1;
     x->expected = mpc_realloc(i, x->expected, sizeof(char*) * x->expected_num);
     x->expected[0] = expect;
     return x;
   }
 
   else if (x->expected_num == 1) {
     expect = mpc_malloc(i, strlen(prefix) + strlen(x->expected[0]) + 1);
     strcpy(expect, prefix);
     strcat(expect, x->expected[0]);
     mpc_free(i, x->expected[0]);
     x->expected[0] = expect;
     return x;
   }
 
   else if (x->expected_num > 1) {
 
     l += strlen(prefix);
     for (j = 0; j < x->expected_num-2; j++) {
       l += strlen(x->expected[j]) + strlen(", ");
     }
     l += strlen(x->expected[x->expected_num-2]);
     l += strlen(" or ");
     l += strlen(x->expected[x->expected_num-1]);
 
     expect = mpc_malloc(i, l + 1);
 
     strcpy(expect, prefix);
     for (j = 0; j < x->expected_num-2; j++) {
       strcat(expect, x->expected[j]); strcat(expect, ", ");
     }
     strcat(expect, x->expected[x->expected_num-2]);
     strcat(expect, " or ");
     strcat(expect, x->expected[x->expected_num-1]);
 
     for (j = 0; j < x->expected_num; j++) { mpc_free(i, x->expected[j]); }
 
     x->expected_num = 1;
     x->expected = mpc_realloc(i, x->expected, sizeof(char*) * x->expected_num);
     x->expected[0] = expect;
     return x;
   }
 
   return NULL;
 }
 
 static mpc_err_t *mpc_err_many1(mpc_input_t *i, mpc_err_t *x) {
   return mpc_err_repeat(i, x, "one or more of ");
 }
 
 static mpc_err_t *mpc_err_count(mpc_input_t *i, mpc_err_t *x, int n) {
   mpc_err_t *y;
   int digits = n/10 + 1;
   char *prefix;
   prefix = mpc_malloc(i, digits + strlen(" of ") + 1);
   if (!prefix) {
     return NULL;
   }
   sprintf(prefix, "%i of ", n);
   y = mpc_err_repeat(i, x, prefix);
   mpc_free(i, prefix);
   return y;
 }
 
 static mpc_err_t *mpc_err_merge(mpc_input_t *i, mpc_err_t *x, mpc_err_t *y) {
   mpc_err_t *errs[2];
   errs[0] = x;
   errs[1] = y;
   return mpc_err_or(i, errs, 2);
 }
 
 /*
 ** Parser Type
 */
 
 enum {
   MPC_TYPE_UNDEFINED  = 0,
   MPC_TYPE_PASS       = 1,
   MPC_TYPE_FAIL       = 2,
   MPC_TYPE_LIFT       = 3,
   MPC_TYPE_LIFT_VAL   = 4,
   MPC_TYPE_EXPECT     = 5,
   MPC_TYPE_ANCHOR     = 6,
   MPC_TYPE_STATE      = 7,
 
   MPC_TYPE_ANY        = 8,
   MPC_TYPE_SINGLE     = 9,
   MPC_TYPE_ONEOF      = 10,
   MPC_TYPE_NONEOF     = 11,
   MPC_TYPE_RANGE      = 12,
   MPC_TYPE_SATISFY    = 13,
   MPC_TYPE_STRING     = 14,
 
   MPC_TYPE_APPLY      = 15,
   MPC_TYPE_APPLY_TO   = 16,
   MPC_TYPE_PREDICT    = 17,
   MPC_TYPE_NOT        = 18,
   MPC_TYPE_MAYBE      = 19,
   MPC_TYPE_MANY       = 20,
   MPC_TYPE_MANY1      = 21,
   MPC_TYPE_COUNT      = 22,
 
   MPC_TYPE_OR         = 23,
   MPC_TYPE_AND        = 24,
 
   MPC_TYPE_CHECK      = 25,
   MPC_TYPE_CHECK_WITH = 26,
 
   MPC_TYPE_SOI        = 27,
   MPC_TYPE_EOI        = 28
 };
 
 typedef struct { char *m; } mpc_pdata_fail_t;
 typedef struct { mpc_ctor_t lf; void *x; } mpc_pdata_lift_t;
 typedef struct { mpc_parser_t *x; char *m; } mpc_pdata_expect_t;
 typedef struct { int(*f)(char,char); } mpc_pdata_anchor_t;
 typedef struct { char x; } mpc_pdata_single_t;
 typedef struct { char x; char y; } mpc_pdata_range_t;
 typedef struct { int(*f)(char); } mpc_pdata_satisfy_t;
 typedef struct { char *x; } mpc_pdata_string_t;
 typedef struct { mpc_parser_t *x; mpc_apply_t f; } mpc_pdata_apply_t;
 typedef struct { mpc_parser_t *x; mpc_apply_to_t f; void *d; } mpc_pdata_apply_to_t;
 typedef struct { mpc_parser_t *x; mpc_dtor_t dx; mpc_check_t f; char *e; } mpc_pdata_check_t;
 typedef struct { mpc_parser_t *x; mpc_dtor_t dx; mpc_check_with_t f; void *d; char *e; } mpc_pdata_check_with_t;
 typedef struct { mpc_parser_t *x; } mpc_pdata_predict_t;
 typedef struct { mpc_parser_t *x; mpc_dtor_t dx; mpc_ctor_t lf; } mpc_pdata_not_t;
 typedef struct { int n; mpc_fold_t f; mpc_parser_t *x; mpc_dtor_t dx; } mpc_pdata_repeat_t;
 typedef struct { int n; mpc_parser_t **xs; } mpc_pdata_or_t;
 typedef struct { int n; mpc_fold_t f; mpc_parser_t **xs; mpc_dtor_t *dxs;  } mpc_pdata_and_t;
 
 typedef union {
   mpc_pdata_fail_t fail;
   mpc_pdata_lift_t lift;
   mpc_pdata_expect_t expect;
   mpc_pdata_anchor_t anchor;
   mpc_pdata_single_t single;
   mpc_pdata_range_t range;
   mpc_pdata_satisfy_t satisfy;
   mpc_pdata_string_t string;
   mpc_pdata_apply_t apply;
   mpc_pdata_apply_to_t apply_to;
   mpc_pdata_check_t check;
   mpc_pdata_check_with_t check_with;
   mpc_pdata_predict_t predict;
   mpc_pdata_not_t not;
   mpc_pdata_repeat_t repeat;
   mpc_pdata_and_t and;
   mpc_pdata_or_t or;
 } mpc_pdata_t;
 
 struct mpc_parser_t {
   char *name;
   mpc_pdata_t data;
   char type;
   char retained;
 };
 
 static mpc_val_t *mpcf_input_nth_free(mpc_input_t *i, int n, mpc_val_t **xs, int x) {
   int j;
   for (j = 0; j < n; j++) { if (j != x) { mpc_free(i, xs[j]); } }
   return xs[x];
 }
 
 static mpc_val_t *mpcf_input_fst_free(mpc_input_t *i, int n, mpc_val_t **xs) { return mpcf_input_nth_free(i, n, xs, 0); }
 static mpc_val_t *mpcf_input_snd_free(mpc_input_t *i, int n, mpc_val_t **xs) { return mpcf_input_nth_free(i, n, xs, 1); }
 static mpc_val_t *mpcf_input_trd_free(mpc_input_t *i, int n, mpc_val_t **xs) { return mpcf_input_nth_free(i, n, xs, 2); }
 
 static mpc_val_t *mpcf_input_strfold(mpc_input_t *i, int n, mpc_val_t **xs) {
   int j;
   size_t l = 0;
   if (n == 0) { return mpc_calloc(i, 1, 1); }
   for (j = 0; j < n; j++) { l += strlen(xs[j]); }
   xs[0] = mpc_realloc(i, xs[0], l + 1);
   for (j = 1; j < n; j++) { strcat(xs[0], xs[j]); mpc_free(i, xs[j]); }
   return xs[0];
 }
 
 static mpc_val_t *mpcf_input_state_ast(mpc_input_t *i, int n, mpc_val_t **xs) {
   mpc_state_t *s = ((mpc_state_t**)xs)[0];
   mpc_ast_t *a = ((mpc_ast_t**)xs)[1];
   a = mpc_ast_state(a, *s);
   mpc_free(i, s);
   (void) n;
   return a;
 }
 
 static mpc_val_t *mpc_parse_fold(mpc_input_t *i, mpc_fold_t f, int n, mpc_val_t **xs) {
   int j;
   if (f == mpcf_null)      { return mpcf_null(n, xs); }
   if (f == mpcf_fst)       { return mpcf_fst(n, xs); }
   if (f == mpcf_snd)       { return mpcf_snd(n, xs); }
   if (f == mpcf_trd)       { return mpcf_trd(n, xs); }
   if (f == mpcf_fst_free)  { return mpcf_input_fst_free(i, n, xs); }
   if (f == mpcf_snd_free)  { return mpcf_input_snd_free(i, n, xs); }
   if (f == mpcf_trd_free)  { return mpcf_input_trd_free(i, n, xs); }
   if (f == mpcf_strfold)   { return mpcf_input_strfold(i, n, xs); }
   if (f == mpcf_state_ast) { return mpcf_input_state_ast(i, n, xs); }
   for (j = 0; j < n; j++) { xs[j] = mpc_export(i, xs[j]); }
   return f(j, xs);
 }
 
 static mpc_val_t *mpcf_input_free(mpc_input_t *i, mpc_val_t *x) {
   mpc_free(i, x);
   return NULL;
 }
 
 static mpc_val_t *mpcf_input_str_ast(mpc_input_t *i, mpc_val_t *c) {
   mpc_ast_t *a = mpc_ast_new("", c);
   mpc_free(i, c);
   return a;
 }
 
 static mpc_val_t *mpc_parse_apply(mpc_input_t *i, mpc_apply_t f, mpc_val_t *x) {
   if (f == mpcf_free)     { return mpcf_input_free(i, x); }
   if (f == mpcf_str_ast)  { return mpcf_input_str_ast(i, x); }
   return f(mpc_export(i, x));
 }
 
 static mpc_val_t *mpc_parse_apply_to(mpc_input_t *i, mpc_apply_to_t f, mpc_val_t *x, mpc_val_t *d) {
   return f(mpc_export(i, x), d);
 }
 
 static void mpc_parse_dtor(mpc_input_t *i, mpc_dtor_t d, mpc_val_t *x) {
   if (d == free) { mpc_free(i, x); return; }
   d(mpc_export(i, x));
 }
 
 enum {
   MPC_PARSE_STACK_MIN = 4
 };
 
 #define MPC_SUCCESS(x) r->output = x; return 1
 #define MPC_FAILURE(x) r->error = x; return 0
 #define MPC_PRIMITIVE(x) \
   if (x) { MPC_SUCCESS(r->output); } \
   else { MPC_FAILURE(NULL); }
 
 #define MPC_MAX_RECURSION_DEPTH 1000
 
 static int mpc_parse_run(mpc_input_t *i, mpc_parser_t *p, mpc_result_t *r, mpc_err_t **e, int depth) {
 
   int j = 0, k = 0;
   mpc_result_t results_stk[MPC_PARSE_STACK_MIN];
   mpc_result_t *results;
   int results_slots = MPC_PARSE_STACK_MIN;
 
   if (depth == MPC_MAX_RECURSION_DEPTH)
   {
     MPC_FAILURE(mpc_err_fail(i, "Maximum recursion depth exceeded!"));
   }
 
   switch (p->type) {
 
     /* Basic Parsers */
 
     case MPC_TYPE_ANY:     MPC_PRIMITIVE(mpc_input_any(i, (char**)&r->output));
     case MPC_TYPE_SINGLE:  MPC_PRIMITIVE(mpc_input_char(i, p->data.single.x, (char**)&r->output));
     case MPC_TYPE_RANGE:   MPC_PRIMITIVE(mpc_input_range(i, p->data.range.x, p->data.range.y, (char**)&r->output));
     case MPC_TYPE_ONEOF:   MPC_PRIMITIVE(mpc_input_oneof(i, p->data.string.x, (char**)&r->output));
     case MPC_TYPE_NONEOF:  MPC_PRIMITIVE(mpc_input_noneof(i, p->data.string.x, (char**)&r->output));
     case MPC_TYPE_SATISFY: MPC_PRIMITIVE(mpc_input_satisfy(i, p->data.satisfy.f, (char**)&r->output));
     case MPC_TYPE_STRING:  MPC_PRIMITIVE(mpc_input_string(i, p->data.string.x, (char**)&r->output));
     case MPC_TYPE_ANCHOR:  MPC_PRIMITIVE(mpc_input_anchor(i, p->data.anchor.f, (char**)&r->output));
     case MPC_TYPE_SOI:     MPC_PRIMITIVE(mpc_input_soi(i, (char**)&r->output));
     case MPC_TYPE_EOI:     MPC_PRIMITIVE(mpc_input_eoi(i, (char**)&r->output));
 
     /* Other parsers */
 
     case MPC_TYPE_UNDEFINED: MPC_FAILURE(mpc_err_fail(i, "Parser Undefined!"));
     case MPC_TYPE_PASS:      MPC_SUCCESS(NULL);
     case MPC_TYPE_FAIL:      MPC_FAILURE(mpc_err_fail(i, p->data.fail.m));
     case MPC_TYPE_LIFT:      MPC_SUCCESS(p->data.lift.lf());
     case MPC_TYPE_LIFT_VAL:  MPC_SUCCESS(p->data.lift.x);
     case MPC_TYPE_STATE:     MPC_SUCCESS(mpc_input_state_copy(i));
 
     /* Application Parsers */
 
     case MPC_TYPE_APPLY:
       if (mpc_parse_run(i, p->data.apply.x, r, e, depth+1)) {
         MPC_SUCCESS(mpc_parse_apply(i, p->data.apply.f, r->output));
       } else {
         MPC_FAILURE(r->output);
       }
 
     case MPC_TYPE_APPLY_TO:
       if (mpc_parse_run(i, p->data.apply_to.x, r, e, depth+1)) {
         MPC_SUCCESS(mpc_parse_apply_to(i, p->data.apply_to.f, r->output, p->data.apply_to.d));
       } else {
         MPC_FAILURE(r->error);
       }
 
     case MPC_TYPE_CHECK:
       if (mpc_parse_run(i, p->data.check.x, r, e, depth+1)) {
         if (p->data.check.f(&r->output)) {
           MPC_SUCCESS(r->output);
         } else {
           mpc_parse_dtor(i, p->data.check.dx, r->output);
           MPC_FAILURE(mpc_err_fail(i, p->data.check.e));
         }
       } else {
         MPC_FAILURE(r->error);
       }
 
     case MPC_TYPE_CHECK_WITH:
       if (mpc_parse_run(i, p->data.check_with.x, r, e, depth+1)) {
         if (p->data.check_with.f(&r->output, p->data.check_with.d)) {
           MPC_SUCCESS(r->output);
         } else {
           mpc_parse_dtor(i, p->data.check.dx, r->output);
           MPC_FAILURE(mpc_err_fail(i, p->data.check_with.e));
         }
       } else {
         MPC_FAILURE(r->error);
       }
 
     case MPC_TYPE_EXPECT:
       mpc_input_suppress_enable(i);
       if (mpc_parse_run(i, p->data.expect.x, r, e, depth+1)) {
         mpc_input_suppress_disable(i);
         MPC_SUCCESS(r->output);
       } else {
         mpc_input_suppress_disable(i);
         MPC_FAILURE(mpc_err_new(i, p->data.expect.m));
       }
 
     case MPC_TYPE_PREDICT:
       mpc_input_backtrack_disable(i);
       if (mpc_parse_run(i, p->data.predict.x, r, e, depth+1)) {
         mpc_input_backtrack_enable(i);
         MPC_SUCCESS(r->output);
       } else {
         mpc_input_backtrack_enable(i);
         MPC_FAILURE(r->error);
       }
 
     /* Optional Parsers */
 
     /* TODO: Update Not Error Message */
 
     case MPC_TYPE_NOT:
       mpc_input_mark(i);
       mpc_input_suppress_enable(i);
       if (mpc_parse_run(i, p->data.not.x, r, e, depth+1)) {
         mpc_input_rewind(i);
         mpc_input_suppress_disable(i);
         mpc_parse_dtor(i, p->data.not.dx, r->output);
         MPC_FAILURE(mpc_err_new(i, "opposite"));
       } else {
         mpc_input_unmark(i);
         mpc_input_suppress_disable(i);
         MPC_SUCCESS(p->data.not.lf());
       }
 
     case MPC_TYPE_MAYBE:
       if (mpc_parse_run(i, p->data.not.x, r, e, depth+1)) {
         MPC_SUCCESS(r->output);
       } else {
         *e = mpc_err_merge(i, *e, r->error);
         MPC_SUCCESS(p->data.not.lf());
       }
 
     /* Repeat Parsers */
 
     case MPC_TYPE_MANY:
 
       results = results_stk;
 
       while (mpc_parse_run(i, p->data.repeat.x, &results[j], e, depth+1)) {
         j++;
         if (j == MPC_PARSE_STACK_MIN) {
           results_slots = j + j / 2;
           results = mpc_malloc(i, sizeof(mpc_result_t) * results_slots);
           memcpy(results, results_stk, sizeof(mpc_result_t) * MPC_PARSE_STACK_MIN);
         } else if (j >= results_slots) {
           results_slots = j + j / 2;
           results = mpc_realloc(i, results, sizeof(mpc_result_t) * results_slots);
         }
       }
 
       *e = mpc_err_merge(i, *e, results[j].error);
 
       MPC_SUCCESS(
         mpc_parse_fold(i, p->data.repeat.f, j, (mpc_val_t**)results);
         if (j >= MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
 
     case MPC_TYPE_MANY1:
 
       results = results_stk;
 
       while (mpc_parse_run(i, p->data.repeat.x, &results[j], e, depth+1)) {
         j++;
         if (j == MPC_PARSE_STACK_MIN) {
           results_slots = j + j / 2;
           results = mpc_malloc(i, sizeof(mpc_result_t) * results_slots);
           memcpy(results, results_stk, sizeof(mpc_result_t) * MPC_PARSE_STACK_MIN);
         } else if (j >= results_slots) {
           results_slots = j + j / 2;
           results = mpc_realloc(i, results, sizeof(mpc_result_t) * results_slots);
         }
       }
 
       if (j == 0) {
         MPC_FAILURE(
           mpc_err_many1(i, results[j].error);
           if (j >= MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
       } else {
 
         *e = mpc_err_merge(i, *e, results[j].error);
 
         MPC_SUCCESS(
           mpc_parse_fold(i, p->data.repeat.f, j, (mpc_val_t**)results);
           if (j >= MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
       }
 
     case MPC_TYPE_COUNT:
 
       results = p->data.repeat.n > MPC_PARSE_STACK_MIN
         ? mpc_malloc(i, sizeof(mpc_result_t) * p->data.repeat.n)
         : results_stk;
 
       while (mpc_parse_run(i, p->data.repeat.x, &results[j], e, depth+1)) {
         j++;
         if (j == p->data.repeat.n) { break; }
       }
 
       if (j == p->data.repeat.n) {
         MPC_SUCCESS(
           mpc_parse_fold(i, p->data.repeat.f, j, (mpc_val_t**)results);
           if (p->data.repeat.n > MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
       } else {
         for (k = 0; k < j; k++) {
           mpc_parse_dtor(i, p->data.repeat.dx, results[k].output);
         }
         MPC_FAILURE(
           mpc_err_count(i, results[j].error, p->data.repeat.n);
           if (p->data.repeat.n > MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
       }
 
     /* Combinatory Parsers */
 
     case MPC_TYPE_OR:
 
       if (p->data.or.n == 0) { MPC_SUCCESS(NULL); }
 
       results = p->data.or.n > MPC_PARSE_STACK_MIN
         ? mpc_malloc(i, sizeof(mpc_result_t) * p->data.or.n)
         : results_stk;
 
       for (j = 0; j < p->data.or.n; j++) {
         if (mpc_parse_run(i, p->data.or.xs[j], &results[j], e, depth+1)) {
           MPC_SUCCESS(results[j].output;
             if (p->data.or.n > MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
         } else {
           *e = mpc_err_merge(i, *e, results[j].error);
         }
       }
 
       MPC_FAILURE(NULL;
         if (p->data.or.n > MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
 
     case MPC_TYPE_AND:
 
       if (p->data.and.n == 0) { MPC_SUCCESS(NULL); }
 
       results = p->data.or.n > MPC_PARSE_STACK_MIN
         ? mpc_malloc(i, sizeof(mpc_result_t) * p->data.or.n)
         : results_stk;
 
       mpc_input_mark(i);
       for (j = 0; j < p->data.and.n; j++) {
         if (!mpc_parse_run(i, p->data.and.xs[j], &results[j], e, depth+1)) {
           mpc_input_rewind(i);
           for (k = 0; k < j; k++) {
             mpc_parse_dtor(i, p->data.and.dxs[k], results[k].output);
           }
           MPC_FAILURE(results[j].error;
             if (p->data.or.n > MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
         }
       }
       mpc_input_unmark(i);
       MPC_SUCCESS(
         mpc_parse_fold(i, p->data.and.f, j, (mpc_val_t**)results);
         if (p->data.or.n > MPC_PARSE_STACK_MIN) { mpc_free(i, results); });
 
     /* End */
 
     default:
 
       MPC_FAILURE(mpc_err_fail(i, "Unknown Parser Type Id!"));
   }
 
   return 0;
 
 }
 
 #undef MPC_SUCCESS
 #undef MPC_FAILURE
 #undef MPC_PRIMITIVE
 
 int mpc_parse_input(mpc_input_t *i, mpc_parser_t *p, mpc_result_t *r) {
   int x;
   mpc_err_t *e = mpc_err_fail(i, "Unknown Error");
   e->state = mpc_state_invalid();
   x = mpc_parse_run(i, p, r, &e, 0);
   if (x) {
     mpc_err_delete_internal(i, e);
     r->output = mpc_export(i, r->output);
   } else {
     r->error = mpc_err_export(i, mpc_err_merge(i, e, r->error));
   }
   return x;
 }
 
 int mpc_parse(const char *filename, const char *string, mpc_parser_t *p, mpc_result_t *r) {
   int x;
   mpc_input_t *i = mpc_input_new_string(filename, string);
   x = mpc_parse_input(i, p, r);
   mpc_input_delete(i);
   return x;
 }
 
 int mpc_nparse(const char *filename, const char *string, size_t length, mpc_parser_t *p, mpc_result_t *r) {
   int x;
   mpc_input_t *i = mpc_input_new_nstring(filename, string, length);
   x = mpc_parse_input(i, p, r);
   mpc_input_delete(i);
   return x;
 }
 
 int mpc_parse_file(const char *filename, FILE *file, mpc_parser_t *p, mpc_result_t *r) {
   int x;
   mpc_input_t *i = mpc_input_new_file(filename, file);
   x = mpc_parse_input(i, p, r);
   mpc_input_delete(i);
   return x;
 }
 
 int mpc_parse_pipe(const char *filename, FILE *pipe, mpc_parser_t *p, mpc_result_t *r) {
   int x;
   mpc_input_t *i = mpc_input_new_pipe(filename, pipe);
   x = mpc_parse_input(i, p, r);
   mpc_input_delete(i);
   return x;
 }
 
 int mpc_parse_contents(const char *filename, mpc_parser_t *p, mpc_result_t *r) {
 
   FILE *f = fopen(filename, "rb");
   int res;
 
   if (f == NULL) {
     r->output = NULL;
     r->error = mpc_err_file(filename, "Unable to open file!");
     return 0;
   }
 
   res = mpc_parse_file(filename, f, p, r);
   fclose(f);
   return res;
 }
 
 /*
 ** Building a Parser
 */
 
 static void mpc_undefine_unretained(mpc_parser_t *p, int force);
 
 static void mpc_undefine_or(mpc_parser_t *p) {
 
   int i;
   for (i = 0; i < p->data.or.n; i++) {
     mpc_undefine_unretained(p->data.or.xs[i], 0);
   }
   free(p->data.or.xs);
 
 }
 
 static void mpc_undefine_and(mpc_parser_t *p) {
 
   int i;
   for (i = 0; i < p->data.and.n; i++) {
     mpc_undefine_unretained(p->data.and.xs[i], 0);
   }
   free(p->data.and.xs);
   free(p->data.and.dxs);
 
 }
 
 static void mpc_undefine_unretained(mpc_parser_t *p, int force) {
 
   if (p->retained && !force) { return; }
 
   switch (p->type) {
 
     case MPC_TYPE_FAIL: free(p->data.fail.m); break;
 
     case MPC_TYPE_ONEOF:
     case MPC_TYPE_NONEOF:
     case MPC_TYPE_STRING:
       free(p->data.string.x);
       break;
 
     case MPC_TYPE_APPLY:    mpc_undefine_unretained(p->data.apply.x, 0);    break;
     case MPC_TYPE_APPLY_TO: mpc_undefine_unretained(p->data.apply_to.x, 0); break;
     case MPC_TYPE_PREDICT:  mpc_undefine_unretained(p->data.predict.x, 0);  break;
 
     case MPC_TYPE_MAYBE:
     case MPC_TYPE_NOT:
       mpc_undefine_unretained(p->data.not.x, 0);
       break;
 
     case MPC_TYPE_EXPECT:
       mpc_undefine_unretained(p->data.expect.x, 0);
       free(p->data.expect.m);
       break;
 
     case MPC_TYPE_MANY:
     case MPC_TYPE_MANY1:
     case MPC_TYPE_COUNT:
       mpc_undefine_unretained(p->data.repeat.x, 0);
       break;
 
     case MPC_TYPE_OR:  mpc_undefine_or(p);  break;
     case MPC_TYPE_AND: mpc_undefine_and(p); break;
 
     case MPC_TYPE_CHECK:
       mpc_undefine_unretained(p->data.check.x, 0);
       free(p->data.check.e);
       break;
 
     case MPC_TYPE_CHECK_WITH:
       mpc_undefine_unretained(p->data.check_with.x, 0);
       free(p->data.check_with.e);
       break;
 
     default: break;
   }
 
   if (!force) {
     free(p->name);
     free(p);
   }
 
 }
 
 void mpc_delete(mpc_parser_t *p) {
   if (p->retained) {
 
     if (p->type != MPC_TYPE_UNDEFINED) {
       mpc_undefine_unretained(p, 0);
     }
 
     free(p->name);
     free(p);
 
   } else {
     mpc_undefine_unretained(p, 0);
   }
 }
 
 static void mpc_soft_delete(mpc_val_t *x) {
   mpc_undefine_unretained(x, 0);
 }
 
 static mpc_parser_t *mpc_undefined(void) {
   mpc_parser_t *p = calloc(1, sizeof(mpc_parser_t));
   p->retained = 0;
   p->type = MPC_TYPE_UNDEFINED;
   p->name = NULL;
   return p;
 }
 
 mpc_parser_t *mpc_new(const char *name) {
   mpc_parser_t *p = mpc_undefined();
   p->retained = 1;
   p->name = realloc(p->name, strlen(name) + 1);
   strcpy(p->name, name);
   return p;
 }
 
 mpc_parser_t *mpc_copy(mpc_parser_t *a) {
   int i = 0;
   mpc_parser_t *p;
 
   if (a->retained) { return a; }
 
   p = mpc_undefined();
   p->retained = a->retained;
   p->type = a->type;
   p->data = a->data;
 
   if (a->name) {
     p->name = malloc(strlen(a->name)+1);
     strcpy(p->name, a->name);
   }
 
   switch (a->type) {
 
     case MPC_TYPE_FAIL:
       p->data.fail.m = malloc(strlen(a->data.fail.m)+1);
       strcpy(p->data.fail.m, a->data.fail.m);
     break;
 
     case MPC_TYPE_ONEOF:
     case MPC_TYPE_NONEOF:
     case MPC_TYPE_STRING:
       p->data.string.x = malloc(strlen(a->data.string.x)+1);
       strcpy(p->data.string.x, a->data.string.x);
       break;
 
     case MPC_TYPE_APPLY:    p->data.apply.x    = mpc_copy(a->data.apply.x);    break;
     case MPC_TYPE_APPLY_TO: p->data.apply_to.x = mpc_copy(a->data.apply_to.x); break;
     case MPC_TYPE_PREDICT:  p->data.predict.x  = mpc_copy(a->data.predict.x);  break;
 
     case MPC_TYPE_MAYBE:
     case MPC_TYPE_NOT:
       p->data.not.x = mpc_copy(a->data.not.x);
       break;
 
     case MPC_TYPE_EXPECT:
       p->data.expect.x = mpc_copy(a->data.expect.x);
       p->data.expect.m = malloc(strlen(a->data.expect.m)+1);
       strcpy(p->data.expect.m, a->data.expect.m);
       break;
 
     case MPC_TYPE_MANY:
     case MPC_TYPE_MANY1:
     case MPC_TYPE_COUNT:
       p->data.repeat.x = mpc_copy(a->data.repeat.x);
       break;
 
     case MPC_TYPE_OR:
       p->data.or.xs = malloc(a->data.or.n * sizeof(mpc_parser_t*));
       for (i = 0; i < a->data.or.n; i++) {
         p->data.or.xs[i] = mpc_copy(a->data.or.xs[i]);
       }
     break;
     case MPC_TYPE_AND:
       p->data.and.xs = malloc(a->data.and.n * sizeof(mpc_parser_t*));
       for (i = 0; i < a->data.and.n; i++) {
         p->data.and.xs[i] = mpc_copy(a->data.and.xs[i]);
       }
       p->data.and.dxs = malloc((a->data.and.n-1) * sizeof(mpc_dtor_t));
       for (i = 0; i < a->data.and.n-1; i++) {
         p->data.and.dxs[i] = a->data.and.dxs[i];
       }
     break;
 
     case MPC_TYPE_CHECK:
       p->data.check.x      = mpc_copy(a->data.check.x);
       p->data.check.e      = malloc(strlen(a->data.check.e)+1);
       strcpy(p->data.check.e, a->data.check.e);
       break;
     case MPC_TYPE_CHECK_WITH:
       p->data.check_with.x = mpc_copy(a->data.check_with.x);
       p->data.check_with.e = malloc(strlen(a->data.check_with.e)+1);
       strcpy(p->data.check_with.e, a->data.check_with.e);
       break;
 
     default: break;
   }
 
 
   return p;
 }
 
 mpc_parser_t *mpc_undefine(mpc_parser_t *p) {
   mpc_undefine_unretained(p, 1);
   p->type = MPC_TYPE_UNDEFINED;
   return p;
 }
 
 mpc_parser_t *mpc_define(mpc_parser_t *p, mpc_parser_t *a) {
 
   if (p->retained) {
     p->type = a->type;
     p->data = a->data;
   } else {
     mpc_parser_t *a2 = mpc_failf("Attempt to assign to Unretained Parser!");
     p->type = a2->type;
     p->data = a2->data;
     free(a2);
   }
 
   free(a);
   return p;
 }
 
 void mpc_cleanup(int n, ...) {
   int i;
   mpc_parser_t **list = malloc(sizeof(mpc_parser_t*) * n);
 
   va_list va;
   va_start(va, n);
   for (i = 0; i < n; i++) { list[i] = va_arg(va, mpc_parser_t*); }
   for (i = 0; i < n; i++) { mpc_undefine(list[i]); }
   for (i = 0; i < n; i++) { mpc_delete(list[i]); }
   va_end(va);
 
   free(list);
 }
 
 mpc_parser_t *mpc_pass(void) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_PASS;
   return p;
 }
 
 mpc_parser_t *mpc_fail(const char *m) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_FAIL;
   p->data.fail.m = malloc(strlen(m) + 1);
   strcpy(p->data.fail.m, m);
   return p;
 }
 
 /*
 ** As `snprintf` is not ANSI standard this
 ** function `mpc_failf` should be considered
 ** unsafe.
 **
 ** You have a few options if this is going to be
 ** trouble.
 **
 ** - Ensure the format string does not exceed
 **   the buffer length using precision specifiers
 **   such as `%.512s`.
 **
 ** - Patch this function in your code base to
 **   use `snprintf` or whatever variant your
 **   system supports.
 **
 ** - Avoid it altogether.
 **
 */
 
 mpc_parser_t *mpc_failf(const char *fmt, ...) {
 
   va_list va;
   char *buffer;
 
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_FAIL;
 
   va_start(va, fmt);
   buffer = malloc(2048);
   if (!buffer) {
     return NULL;
   }
   vsprintf(buffer, fmt, va);
   va_end(va);
 
   buffer = realloc(buffer, strlen(buffer) + 1);
   p->data.fail.m = buffer;
   return p;
 
 }
 
 mpc_parser_t *mpc_lift_val(mpc_val_t *x) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_LIFT_VAL;
   p->data.lift.x = x;
   return p;
 }
 
 mpc_parser_t *mpc_lift(mpc_ctor_t lf) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_LIFT;
   p->data.lift.lf = lf;
   return p;
 }
 
 mpc_parser_t *mpc_anchor(int(*f)(char,char)) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_ANCHOR;
   p->data.anchor.f = f;
   return mpc_expect(p, "anchor");
 }
 
 mpc_parser_t *mpc_state(void) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_STATE;
   return p;
 }
 
 mpc_parser_t *mpc_expect(mpc_parser_t *a, const char *expected) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_EXPECT;
   p->data.expect.x = a;
   p->data.expect.m = malloc(strlen(expected) + 1);
   strcpy(p->data.expect.m, expected);
   return p;
 }
 
 /*
 ** As `snprintf` is not ANSI standard this
 ** function `mpc_expectf` should be considered
 ** unsafe.
 **
 ** You have a few options if this is going to be
 ** trouble.
 **
 ** - Ensure the format string does not exceed
 **   the buffer length using precision specifiers
 **   such as `%.512s`.
 **
 ** - Patch this function in your code base to
 **   use `snprintf` or whatever variant your
 **   system supports.
 **
 ** - Avoid it altogether.
 **
 */
 
 mpc_parser_t *mpc_expectf(mpc_parser_t *a, const char *fmt, ...) {
   va_list va;
   char *buffer;
 
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_EXPECT;
 
   va_start(va, fmt);
   buffer = malloc(2048);
   if (!buffer) {
     return NULL;
   }
   vsprintf(buffer, fmt, va);
   va_end(va);
 
   buffer = realloc(buffer, strlen(buffer) + 1);
   p->data.expect.x = a;
   p->data.expect.m = buffer;
   return p;
 }
 
 /*
 ** Basic Parsers
 */
 
 mpc_parser_t *mpc_any(void) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_ANY;
   return mpc_expect(p, "any character");
 }
 
 mpc_parser_t *mpc_char(char c) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_SINGLE;
   p->data.single.x = c;
   return mpc_expectf(p, "'%c'", c);
 }
 
 mpc_parser_t *mpc_range(char s, char e) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_RANGE;
   p->data.range.x = s;
   p->data.range.y = e;
   return mpc_expectf(p, "character between '%c' and '%c'", s, e);
 }
 
 mpc_parser_t *mpc_oneof(const char *s) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_ONEOF;
   p->data.string.x = malloc(strlen(s) + 1);
   strcpy(p->data.string.x, s);
   return mpc_expectf(p, "one of '%s'", s);
 }
 
 mpc_parser_t *mpc_noneof(const char *s) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_NONEOF;
   p->data.string.x = malloc(strlen(s) + 1);
   strcpy(p->data.string.x, s);
   return mpc_expectf(p, "none of '%s'", s);
 
 }
 
 mpc_parser_t *mpc_satisfy(int(*f)(char)) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_SATISFY;
   p->data.satisfy.f = f;
   return mpc_expectf(p, "character satisfying function %p", f);
 }
 
 mpc_parser_t *mpc_string(const char *s) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_STRING;
   p->data.string.x = malloc(strlen(s) + 1);
   strcpy(p->data.string.x, s);
   return mpc_expectf(p, "\"%s\"", s);
 }
 
 /*
 ** Core Parsers
 */
 
 mpc_parser_t *mpc_apply(mpc_parser_t *a, mpc_apply_t f) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_APPLY;
   p->data.apply.x = a;
   p->data.apply.f = f;
   return p;
 }
 
 mpc_parser_t *mpc_apply_to(mpc_parser_t *a, mpc_apply_to_t f, void *x) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_APPLY_TO;
   p->data.apply_to.x = a;
   p->data.apply_to.f = f;
   p->data.apply_to.d = x;
   return p;
 }
 
 mpc_parser_t *mpc_check(mpc_parser_t *a, mpc_dtor_t da, mpc_check_t f, const char *e) {
   mpc_parser_t  *p = mpc_undefined();
   p->type = MPC_TYPE_CHECK;
   p->data.check.x = a;
   p->data.check.dx = da;
   p->data.check.f = f;
   p->data.check.e = malloc(strlen(e) + 1);
   strcpy(p->data.check.e, e);
   return p;
 }
 
 mpc_parser_t *mpc_check_with(mpc_parser_t *a, mpc_dtor_t da, mpc_check_with_t f, void *x, const char *e) {
   mpc_parser_t  *p = mpc_undefined();
   p->type = MPC_TYPE_CHECK_WITH;
   p->data.check_with.x = a;
   p->data.check_with.dx = da;
   p->data.check_with.f = f;
   p->data.check_with.d = x;
   p->data.check_with.e = malloc(strlen(e) + 1);
   strcpy(p->data.check_with.e, e);
   return p;
 }
 
 mpc_parser_t *mpc_checkf(mpc_parser_t *a, mpc_dtor_t da, mpc_check_t f, const char *fmt, ...) {
   va_list va;
   char *buffer;
   mpc_parser_t *p;
 
   va_start(va, fmt);
   buffer = malloc(2048);
   vsprintf(buffer, fmt, va);
   va_end(va);
 
   p = mpc_check(a, da, f, buffer);
   free(buffer);
 
   return p;
 }
 
 mpc_parser_t *mpc_check_withf(mpc_parser_t *a, mpc_dtor_t da, mpc_check_with_t f, void *x, const char *fmt, ...) {
   va_list va;
   char *buffer;
   mpc_parser_t *p;
 
   va_start(va, fmt);
   buffer = malloc(2048);
   vsprintf(buffer, fmt, va);
   va_end(va);
 
   p = mpc_check_with(a, da, f, x, buffer);
   free(buffer);
 
   return p;
 }
 
 mpc_parser_t *mpc_predictive(mpc_parser_t *a) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_PREDICT;
   p->data.predict.x = a;
   return p;
 }
 
 mpc_parser_t *mpc_not_lift(mpc_parser_t *a, mpc_dtor_t da, mpc_ctor_t lf) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_NOT;
   p->data.not.x = a;
   p->data.not.dx = da;
   p->data.not.lf = lf;
   return p;
 }
 
 mpc_parser_t *mpc_not(mpc_parser_t *a, mpc_dtor_t da) {
   return mpc_not_lift(a, da, mpcf_ctor_null);
 }
 
 mpc_parser_t *mpc_maybe_lift(mpc_parser_t *a, mpc_ctor_t lf) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_MAYBE;
   p->data.not.x = a;
   p->data.not.lf = lf;
   return p;
 }
 
 mpc_parser_t *mpc_maybe(mpc_parser_t *a) {
   return mpc_maybe_lift(a, mpcf_ctor_null);
 }
 
 mpc_parser_t *mpc_many(mpc_fold_t f, mpc_parser_t *a) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_MANY;
   p->data.repeat.x = a;
   p->data.repeat.f = f;
   return p;
 }
 
 mpc_parser_t *mpc_many1(mpc_fold_t f, mpc_parser_t *a) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_MANY1;
   p->data.repeat.x = a;
   p->data.repeat.f = f;
   return p;
 }
 
 mpc_parser_t *mpc_count(int n, mpc_fold_t f, mpc_parser_t *a, mpc_dtor_t da) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_COUNT;
   p->data.repeat.n = n;
   p->data.repeat.f = f;
   p->data.repeat.x = a;
   p->data.repeat.dx = da;
   return p;
 }
 
 mpc_parser_t *mpc_or(int n, ...) {
 
   int i;
   va_list va;
 
   mpc_parser_t *p = mpc_undefined();
 
   p->type = MPC_TYPE_OR;
   p->data.or.n = n;
   p->data.or.xs = malloc(sizeof(mpc_parser_t*) * n);
 
   va_start(va, n);
   for (i = 0; i < n; i++) {
     p->data.or.xs[i] = va_arg(va, mpc_parser_t*);
   }
   va_end(va);
 
   return p;
 }
 
 mpc_parser_t *mpc_and(int n, mpc_fold_t f, ...) {
 
   int i;
   va_list va;
 
   mpc_parser_t *p = mpc_undefined();
 
   p->type = MPC_TYPE_AND;
   p->data.and.n = n;
   p->data.and.f = f;
   p->data.and.xs = malloc(sizeof(mpc_parser_t*) * n);
   p->data.and.dxs = malloc(sizeof(mpc_dtor_t) * (n-1));
 
   va_start(va, f);
   for (i = 0; i < n; i++) {
     p->data.and.xs[i] = va_arg(va, mpc_parser_t*);
   }
   for (i = 0; i < (n-1); i++) {
     p->data.and.dxs[i] = va_arg(va, mpc_dtor_t);
   }
   va_end(va);
 
   return p;
 }
 
 /*
 ** Common Parsers
 */
 
 mpc_parser_t *mpc_soi(void) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_SOI;
   return mpc_expect(p, "start of input");
 }
 
 mpc_parser_t *mpc_eoi(void) {
   mpc_parser_t *p = mpc_undefined();
   p->type = MPC_TYPE_EOI;
   return mpc_expect(p, "end of input");
 }
 
 static int mpc_boundary_anchor(char prev, char next) {
   const char* word = "abcdefghijklmnopqrstuvwxyz"
                      "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
                      "0123456789_";
   if ( strchr(word, next) &&  prev == '\0') { return 1; }
   if ( strchr(word, prev) &&  next == '\0') { return 1; }
   if ( strchr(word, next) && !strchr(word, prev)) { return 1; }
   if (!strchr(word, next) &&  strchr(word, prev)) { return 1; }
   return 0;
 }
 
 static int mpc_boundary_newline_anchor(char prev, char next) {
   (void)next;
   return prev == '\n';
 }
 
 mpc_parser_t *mpc_boundary(void) { return mpc_expect(mpc_anchor(mpc_boundary_anchor), "word boundary"); }
 mpc_parser_t *mpc_boundary_newline(void) { return mpc_expect(mpc_anchor(mpc_boundary_newline_anchor), "start of newline"); }
 
 mpc_parser_t *mpc_whitespace(void) { return mpc_expect(mpc_oneof(" \f\n\r\t\v"), "whitespace"); }
 mpc_parser_t *mpc_whitespaces(void) { return mpc_expect(mpc_many(mpcf_strfold, mpc_whitespace()), "spaces"); }
 mpc_parser_t *mpc_blank(void) { return mpc_expect(mpc_apply(mpc_whitespaces(), mpcf_free), "whitespace"); }
 
 mpc_parser_t *mpc_newline(void) { return mpc_expect(mpc_char('\n'), "newline"); }
 mpc_parser_t *mpc_tab(void) { return mpc_expect(mpc_char('\t'), "tab"); }
 mpc_parser_t *mpc_escape(void) { return mpc_and(2, mpcf_strfold, mpc_char('\\'), mpc_any(), free); }
 
 mpc_parser_t *mpc_digit(void) { return mpc_expect(mpc_oneof("0123456789"), "digit"); }
 mpc_parser_t *mpc_hexdigit(void) { return mpc_expect(mpc_oneof("0123456789ABCDEFabcdef"), "hex digit"); }
 mpc_parser_t *mpc_octdigit(void) { return mpc_expect(mpc_oneof("01234567"), "oct digit"); }
 mpc_parser_t *mpc_digits(void) { return mpc_expect(mpc_many1(mpcf_strfold, mpc_digit()), "digits"); }
 mpc_parser_t *mpc_hexdigits(void) { return mpc_expect(mpc_many1(mpcf_strfold, mpc_hexdigit()), "hex digits"); }
 mpc_parser_t *mpc_octdigits(void) { return mpc_expect(mpc_many1(mpcf_strfold, mpc_octdigit()), "oct digits"); }
 
 mpc_parser_t *mpc_lower(void) { return mpc_expect(mpc_oneof("abcdefghijklmnopqrstuvwxyz"), "lowercase letter"); }
 mpc_parser_t *mpc_upper(void) { return mpc_expect(mpc_oneof("ABCDEFGHIJKLMNOPQRSTUVWXYZ"), "uppercase letter"); }
 mpc_parser_t *mpc_alpha(void) { return mpc_expect(mpc_oneof("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"), "letter"); }
 mpc_parser_t *mpc_underscore(void) { return mpc_expect(mpc_char('_'), "underscore"); }
 mpc_parser_t *mpc_alphanum(void) { return mpc_expect(mpc_or(3, mpc_alpha(), mpc_digit(), mpc_underscore()), "alphanumeric"); }
 
 mpc_parser_t *mpc_int(void) { return mpc_expect(mpc_apply(mpc_digits(), mpcf_int), "integer"); }
 mpc_parser_t *mpc_hex(void) { return mpc_expect(mpc_apply(mpc_hexdigits(), mpcf_hex), "hexadecimal"); }
 mpc_parser_t *mpc_oct(void) { return mpc_expect(mpc_apply(mpc_octdigits(), mpcf_oct), "octadecimal"); }
 mpc_parser_t *mpc_number(void) { return mpc_expect(mpc_or(3, mpc_int(), mpc_hex(), mpc_oct()), "number"); }
 
 mpc_parser_t *mpc_real(void) {
 
   /* [+-]?\d+(\.\d+)?([eE][+-]?[0-9]+)? */
 
   mpc_parser_t *p0, *p1, *p2, *p30, *p31, *p32, *p3;
 
   p0 = mpc_maybe_lift(mpc_oneof("+-"), mpcf_ctor_str);
   p1 = mpc_digits();
   p2 = mpc_maybe_lift(mpc_and(2, mpcf_strfold, mpc_char('.'), mpc_digits(), free), mpcf_ctor_str);
   p30 = mpc_oneof("eE");
   p31 = mpc_maybe_lift(mpc_oneof("+-"), mpcf_ctor_str);
   p32 = mpc_digits();
   p3 = mpc_maybe_lift(mpc_and(3, mpcf_strfold, p30, p31, p32, free, free), mpcf_ctor_str);
 
   return mpc_expect(mpc_and(4, mpcf_strfold, p0, p1, p2, p3, free, free, free), "real");
 
 }
 
 mpc_parser_t *mpc_float(void) {
   return mpc_expect(mpc_apply(mpc_real(), mpcf_float), "float");
 }
 
 mpc_parser_t *mpc_char_lit(void) {
   return mpc_expect(mpc_between(mpc_or(2, mpc_escape(), mpc_any()), free, "'", "'"), "char");
 }
 
 mpc_parser_t *mpc_string_lit(void) {
   mpc_parser_t *strchar = mpc_or(2, mpc_escape(), mpc_noneof("\""));
   return mpc_expect(mpc_between(mpc_many(mpcf_strfold, strchar), free, "\"", "\""), "string");
 }
 
 mpc_parser_t *mpc_regex_lit(void) {
   mpc_parser_t *regexchar = mpc_or(2, mpc_escape(), mpc_noneof("/"));
   return mpc_expect(mpc_between(mpc_many(mpcf_strfold, regexchar), free, "/", "/"), "regex");
 }
 
 mpc_parser_t *mpc_ident(void) {
   mpc_parser_t *p0, *p1;
   p0 = mpc_or(2, mpc_alpha(), mpc_underscore());
   p1 = mpc_many(mpcf_strfold, mpc_alphanum());
   return mpc_and(2, mpcf_strfold, p0, p1, free);
 }
 
 /*
 ** Useful Parsers
 */
 
 mpc_parser_t *mpc_startwith(mpc_parser_t *a) { return mpc_and(2, mpcf_snd, mpc_soi(), a, mpcf_dtor_null); }
 mpc_parser_t *mpc_endwith(mpc_parser_t *a, mpc_dtor_t da) { return mpc_and(2, mpcf_fst, a, mpc_eoi(), da); }
 mpc_parser_t *mpc_whole(mpc_parser_t *a, mpc_dtor_t da) { return mpc_and(3, mpcf_snd, mpc_soi(), a, mpc_eoi(), mpcf_dtor_null, da); }
 
 mpc_parser_t *mpc_stripl(mpc_parser_t *a) { return mpc_and(2, mpcf_snd, mpc_blank(), a, mpcf_dtor_null); }
 mpc_parser_t *mpc_stripr(mpc_parser_t *a) { return mpc_and(2, mpcf_fst, a, mpc_blank(), mpcf_dtor_null); }
 mpc_parser_t *mpc_strip(mpc_parser_t *a) { return mpc_and(3, mpcf_snd, mpc_blank(), a, mpc_blank(), mpcf_dtor_null, mpcf_dtor_null); }
 mpc_parser_t *mpc_tok(mpc_parser_t *a) { return mpc_and(2, mpcf_fst, a, mpc_blank(), mpcf_dtor_null); }
 mpc_parser_t *mpc_sym(const char *s) { return mpc_tok(mpc_string(s)); }
 
 mpc_parser_t *mpc_total(mpc_parser_t *a, mpc_dtor_t da) { return mpc_whole(mpc_strip(a), da); }
 
 mpc_parser_t *mpc_between(mpc_parser_t *a, mpc_dtor_t ad, const char *o, const char *c) {
   return mpc_and(3, mpcf_snd_free,
     mpc_string(o), a, mpc_string(c),
     free, ad);
 }
 
 mpc_parser_t *mpc_parens(mpc_parser_t *a, mpc_dtor_t ad)   { return mpc_between(a, ad, "(", ")"); }
 mpc_parser_t *mpc_braces(mpc_parser_t *a, mpc_dtor_t ad)   { return mpc_between(a, ad, "<", ">"); }
 mpc_parser_t *mpc_brackets(mpc_parser_t *a, mpc_dtor_t ad) { return mpc_between(a, ad, "{", "}"); }
 mpc_parser_t *mpc_squares(mpc_parser_t *a, mpc_dtor_t ad)  { return mpc_between(a, ad, "[", "]"); }
 
 mpc_parser_t *mpc_tok_between(mpc_parser_t *a, mpc_dtor_t ad, const char *o, const char *c) {
   return mpc_and(3, mpcf_snd_free,
     mpc_sym(o), mpc_tok(a), mpc_sym(c),
     free, ad);
 }
 
 mpc_parser_t *mpc_tok_parens(mpc_parser_t *a, mpc_dtor_t ad)   { return mpc_tok_between(a, ad, "(", ")"); }
 mpc_parser_t *mpc_tok_braces(mpc_parser_t *a, mpc_dtor_t ad)   { return mpc_tok_between(a, ad, "<", ">"); }
 mpc_parser_t *mpc_tok_brackets(mpc_parser_t *a, mpc_dtor_t ad) { return mpc_tok_between(a, ad, "{", "}"); }
 mpc_parser_t *mpc_tok_squares(mpc_parser_t *a, mpc_dtor_t ad)  { return mpc_tok_between(a, ad, "[", "]"); }
 
 /*
 ** Regular Expression Parsers
 */
 
 /*
 ** So here is a cute bootstrapping.
 **
 ** I'm using the previously defined
 ** mpc constructs and functions to
 ** parse the user regex string and
 ** construct a parser from it.
 **
 ** As it turns out lots of the standard
 ** mpc functions look a lot like `fold`
 ** functions and so can be used indirectly
 ** by many of the parsing functions to build
 ** a parser directly - as we are parsing.
 **
 ** This is certainly something that
 ** would be less elegant/interesting
 ** in a two-phase parser which first
 ** builds an AST and then traverses it
 ** to generate the object.
 **
 ** This whole thing acts as a great
 ** case study for how trivial it can be
 ** to write a great parser in a few
 ** lines of code using mpc.
 */
 
 /*
 **
 **  ### Regular Expression Grammar
 **
 **      <regex> : <term> | (<term> "|" <regex>)
 **
 **      <term> : <factor>*
 **
 **      <factor> : <base>
 **               | <base> "*"
 **               | <base> "+"
 **               | <base> "?"
 **               | <base> "{" <digits> "}"
 **
 **      <base> : <char>
 **             | "\" <char>
 **             | "(" <regex> ")"
 **             | "[" <range> "]"
 */
 
 static mpc_val_t *mpcf_re_or(int n, mpc_val_t **xs) {
   (void) n;
   if (xs[1] == NULL) { return xs[0]; }
   else { return mpc_or(2, xs[0], xs[1]); }
 }
 
 static mpc_val_t *mpcf_re_and(int n, mpc_val_t **xs) {
   int i;
   mpc_parser_t *p = mpc_lift(mpcf_ctor_str);
   for (i = 0; i < n; i++) {
     p = mpc_and(2, mpcf_strfold, p, xs[i], free);
   }
   return p;
 }
 
 static mpc_val_t *mpcf_re_repeat(int n, mpc_val_t **xs) {
   int num;
   (void) n;
   if (xs[1] == NULL) { return xs[0]; }
   switch(((char*)xs[1])[0])
   {
     case '*': { free(xs[1]); return mpc_many(mpcf_strfold, xs[0]); }; break;
     case '+': { free(xs[1]); return mpc_many1(mpcf_strfold, xs[0]); }; break;
     case '?': { free(xs[1]); return mpc_maybe_lift(xs[0], mpcf_ctor_str); }; break;
     default:
       num = *(int*)xs[1];
       free(xs[1]);
   }
 
   return mpc_count(num, mpcf_strfold, xs[0], free);
 }
 
 static mpc_parser_t *mpc_re_escape_char(char c) {
   switch (c) {
     case 'a': return mpc_char('\a');
     case 'f': return mpc_char('\f');
     case 'n': return mpc_char('\n');
     case 'r': return mpc_char('\r');
     case 't': return mpc_char('\t');
     case 'v': return mpc_char('\v');
     case 'b': return mpc_and(2, mpcf_snd, mpc_boundary(), mpc_lift(mpcf_ctor_str), free);
     case 'B': return mpc_not_lift(mpc_boundary(), free, mpcf_ctor_str);
     case 'A': return mpc_and(2, mpcf_snd, mpc_soi(), mpc_lift(mpcf_ctor_str), free);
     case 'Z': return mpc_and(2, mpcf_snd, mpc_eoi(), mpc_lift(mpcf_ctor_str), free);
     case 'd': return mpc_digit();
     case 'D': return mpc_not_lift(mpc_digit(), free, mpcf_ctor_str);
     case 's': return mpc_whitespace();
     case 'S': return mpc_not_lift(mpc_whitespace(), free, mpcf_ctor_str);
     case 'w': return mpc_alphanum();
     case 'W': return mpc_not_lift(mpc_alphanum(), free, mpcf_ctor_str);
     default: return NULL;
   }
 }
 
 static mpc_val_t *mpcf_re_escape(mpc_val_t *x, void* data) {
 
   int mode = *((int*)data);
   char *s = x;
   mpc_parser_t *p;
 
   /* Any Character */
   if (s[0] == '.') {
     free(s);
     if (mode & MPC_RE_DOTALL) {
       return mpc_any();
     } else {
       return mpc_expect(mpc_noneof("\n"), "any character except a newline");
     }
   }
 
   /* Start of Input */
   if (s[0] == '^') {
     free(s);
     if (mode & MPC_RE_MULTILINE) {
       return mpc_and(2, mpcf_snd, mpc_or(2, mpc_soi(), mpc_boundary_newline()), mpc_lift(mpcf_ctor_str), free);
     } else {
       return mpc_and(2, mpcf_snd, mpc_soi(), mpc_lift(mpcf_ctor_str), free);
     }
   }
 
   /* End of Input */
   if (s[0] == '$') {
     free(s);
     if (mode & MPC_RE_MULTILINE) {
       return mpc_or(2,
         mpc_newline(),
         mpc_and(2, mpcf_snd, mpc_eoi(), mpc_lift(mpcf_ctor_str), free));
     } else {
       return mpc_or(2,
         mpc_and(2, mpcf_fst, mpc_newline(), mpc_eoi(), free),
         mpc_and(2, mpcf_snd, mpc_eoi(), mpc_lift(mpcf_ctor_str), free));
     }
   }
 
   /* Regex Escape */
   if (s[0] == '\\') {
     p = mpc_re_escape_char(s[1]);
     p = (p == NULL) ? mpc_char(s[1]) : p;
     free(s);
     return p;
   }
 
   /* Regex Standard */
   p = mpc_char(s[0]);
   free(s);
   return p;
 }
 
 static const char *mpc_re_range_escape_char(char c) {
   switch (c) {
     case '-': return "-";
     case 'a': return "\a";
     case 'f': return "\f";
     case 'n': return "\n";
     case 'r': return "\r";
     case 't': return "\t";
     case 'v': return "\v";
     case 'b': return "\b";
     case 'd': return "0123456789";
     case 's': return " \f\n\r\t\v";
     case 'w': return "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
     default: return NULL;
   }
 }
 
 static mpc_val_t *mpcf_re_range(mpc_val_t *x) {
 
   mpc_parser_t *out;
   size_t i, j;
   size_t start, end;
   const char *tmp = NULL;
   const char *s = x;
   int comp = s[0] == '^' ? 1 : 0;
   char *range = calloc(1,1);
 
   if (s[0] == '\0') { free(range); free(x); return mpc_fail("Invalid Regex Range Expression"); }
   if (s[0] == '^' &&
       s[1] == '\0') { free(range); free(x); return mpc_fail("Invalid Regex Range Expression"); }
 
   for (i = comp; i < strlen(s); i++){
 
     /* Regex Range Escape */
     if (s[i] == '\\') {
       tmp = mpc_re_range_escape_char(s[i+1]);
       if (tmp != NULL) {
         range = realloc(range, strlen(range) + strlen(tmp) + 1);
         strcat(range, tmp);
       } else {
         range = realloc(range, strlen(range) + 1 + 1);
         range[strlen(range) + 1] = '\0';
         range[strlen(range) + 0] = s[i+1];
       }
       i++;
     }
 
     /* Regex Range...Range */
     else if (s[i] == '-') {
       if (s[i+1] == '\0' || i == 0) {
           range = realloc(range, strlen(range) + strlen("-") + 1);
           strcat(range, "-");
       } else {
         start = s[i-1]+1;
         end = s[i+1]-1;
         for (j = start; j <= end; j++) {
           range = realloc(range, strlen(range) + 1 + 1 + 1);
           range[strlen(range) + 1] = '\0';
           range[strlen(range) + 0] = (char)j;
         }
       }
     }
 
     /* Regex Range Normal */
     else {
       range = realloc(range, strlen(range) + 1 + 1);
       range[strlen(range) + 1] = '\0';
       range[strlen(range) + 0] = s[i];
     }
 
   }
 
   out = comp == 1 ? mpc_noneof(range) : mpc_oneof(range);
 
   free(x);
   free(range);
 
   return out;
 }
 
 mpc_parser_t *mpc_re(const char *re) {
   return mpc_re_mode(re, MPC_RE_DEFAULT);
 }
 
 mpc_parser_t *mpc_re_mode(const char *re, int mode) {
 
   char *err_msg;
   mpc_parser_t *err_out;
   mpc_result_t r;
   mpc_parser_t *Regex, *Term, *Factor, *Base, *Range, *RegexEnclose;
 
   Regex  = mpc_new("regex");
   Term   = mpc_new("term");
   Factor = mpc_new("factor");
   Base   = mpc_new("base");
   Range  = mpc_new("range");
 
   mpc_define(Regex, mpc_and(2, mpcf_re_or,
     Term,
     mpc_maybe(mpc_and(2, mpcf_snd_free, mpc_char('|'), Regex, free)),
     (mpc_dtor_t)mpc_delete
   ));
 
   mpc_define(Term, mpc_many(mpcf_re_and, Factor));
 
   mpc_define(Factor, mpc_and(2, mpcf_re_repeat,
     Base,
     mpc_or(5,
       mpc_char('*'), mpc_char('+'), mpc_char('?'),
       mpc_brackets(mpc_int(), free),
       mpc_pass()),
     (mpc_dtor_t)mpc_delete
   ));
 
   mpc_define(Base, mpc_or(4,
     mpc_parens(Regex, (mpc_dtor_t)mpc_delete),
     mpc_squares(Range, (mpc_dtor_t)mpc_delete),
     mpc_apply_to(mpc_escape(), mpcf_re_escape, &mode),
     mpc_apply_to(mpc_noneof(")|"), mpcf_re_escape, &mode)
   ));
 
   mpc_define(Range, mpc_apply(
     mpc_many(mpcf_strfold, mpc_or(2, mpc_escape(), mpc_noneof("]"))),
     mpcf_re_range
   ));
 
   RegexEnclose = mpc_whole(mpc_predictive(Regex), (mpc_dtor_t)mpc_delete);
 
   mpc_optimise(RegexEnclose);
   mpc_optimise(Regex);
   mpc_optimise(Term);
   mpc_optimise(Factor);
   mpc_optimise(Base);
   mpc_optimise(Range);
 
   if(!mpc_parse("<mpc_re_compiler>", re, RegexEnclose, &r)) {
     err_msg = mpc_err_string(r.error);
     err_out = mpc_failf("Invalid Regex: %s", err_msg);
     mpc_err_delete(r.error);
     free(err_msg);
     r.output = err_out;
   }
 
   mpc_cleanup(6, RegexEnclose, Regex, Term, Factor, Base, Range);
 
   mpc_optimise(r.output);
 
   return r.output;
 
 }
 
 /*
 ** Common Fold Functions
 */
 
 void mpcf_dtor_null(mpc_val_t *x) { (void) x; return; }
 
 mpc_val_t *mpcf_ctor_null(void) { return NULL; }
 mpc_val_t *mpcf_ctor_str(void) { return calloc(1, 1); }
 mpc_val_t *mpcf_free(mpc_val_t *x) { free(x); return NULL; }
 
 mpc_val_t *mpcf_int(mpc_val_t *x) {
   int *y = malloc(sizeof(int));
   *y = strtol(x, NULL, 10);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_hex(mpc_val_t *x) {
   int *y = malloc(sizeof(int));
   *y = strtol(x, NULL, 16);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_oct(mpc_val_t *x) {
   int *y = malloc(sizeof(int));
   *y = strtol(x, NULL, 8);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_float(mpc_val_t *x) {
   float *y = malloc(sizeof(float));
   *y = strtod(x, NULL);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_strtriml(mpc_val_t *x) {
   char *s = x;
   while (isspace((unsigned char)*s)) {
     memmove(s, s+1, strlen(s));
   }
   return s;
 }
 
 mpc_val_t *mpcf_strtrimr(mpc_val_t *x) {
   char *s = x;
   size_t l = strlen(s);
   while (l > 0 && isspace((unsigned char)s[l-1])) {
     s[l-1] = '\0'; l--;
   }
   return s;
 }
 
 mpc_val_t *mpcf_strtrim(mpc_val_t *x) {
   return mpcf_strtriml(mpcf_strtrimr(x));
 }
 
 static const char mpc_escape_input_c[]  = {
   '\a', '\b', '\f', '\n', '\r',
   '\t', '\v', '\\', '\'', '\"', '\0'};
 
 static const char *mpc_escape_output_c[] = {
   "\\a", "\\b", "\\f", "\\n", "\\r", "\\t",
   "\\v", "\\\\", "\\'", "\\\"", "\\0", NULL};
 
 static const char mpc_escape_input_raw_re[] = { '/' };
 static const char *mpc_escape_output_raw_re[] = { "\\/", NULL };
 
 static const char mpc_escape_input_raw_cstr[] = { '"' };
 static const char *mpc_escape_output_raw_cstr[] = { "\\\"", NULL };
 
 static const char mpc_escape_input_raw_cchar[] = { '\'' };
 static const char *mpc_escape_output_raw_cchar[] = { "\\'", NULL };
 
 static mpc_val_t *mpcf_escape_new(mpc_val_t *x, const char *input, const char **output) {
 
   int i;
   int found;
   char buff[2];
   char *s = x;
   char *y = calloc(1, 1);
 
   while (*s) {
 
     i = 0;
     found = 0;
 
     while (output[i]) {
       if (*s == input[i]) {
         y = realloc(y, strlen(y) + strlen(output[i]) + 1);
         strcat(y, output[i]);
         found = 1;
         break;
       }
       i++;
     }
 
     if (!found) {
       y = realloc(y, strlen(y) + 2);
       buff[0] = *s; buff[1] = '\0';
       strcat(y, buff);
     }
 
     s++;
   }
 
 
   return y;
 }
 
 static mpc_val_t *mpcf_unescape_new(mpc_val_t *x, const char *input, const char **output) {
 
   int i;
   int found = 0;
   char buff[2];
   char *s = x;
   char *y = calloc(1, 1);
 
   while (*s) {
 
     i = 0;
     found = 0;
 
     while (output[i]) {
       if ((*(s+0)) == output[i][0] &&
           (*(s+1)) == output[i][1]) {
         y = realloc(y, strlen(y) + 1 + 1);
         buff[0] = input[i]; buff[1] = '\0';
         strcat(y, buff);
         found = 1;
         s++;
         break;
       }
       i++;
     }
 
     if (!found) {
       y = realloc(y, strlen(y) + 1 + 1);
       buff[0] = *s; buff[1] = '\0';
       strcat(y, buff);
     }
 
     if (*s == '\0') { break; }
     else { s++; }
   }
 
   return y;
 
 }
 
 mpc_val_t *mpcf_escape(mpc_val_t *x) {
   mpc_val_t *y = mpcf_escape_new(x, mpc_escape_input_c, mpc_escape_output_c);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_unescape(mpc_val_t *x) {
   mpc_val_t *y = mpcf_unescape_new(x, mpc_escape_input_c, mpc_escape_output_c);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_escape_regex(mpc_val_t *x) {
   mpc_val_t *y = mpcf_escape_new(x, mpc_escape_input_raw_re, mpc_escape_output_raw_re);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_unescape_regex(mpc_val_t *x) {
   mpc_val_t *y = mpcf_unescape_new(x, mpc_escape_input_raw_re, mpc_escape_output_raw_re);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_escape_string_raw(mpc_val_t *x) {
   mpc_val_t *y = mpcf_escape_new(x, mpc_escape_input_raw_cstr, mpc_escape_output_raw_cstr);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_unescape_string_raw(mpc_val_t *x) {
   mpc_val_t *y = mpcf_unescape_new(x, mpc_escape_input_raw_cstr, mpc_escape_output_raw_cstr);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_escape_char_raw(mpc_val_t *x) {
   mpc_val_t *y = mpcf_escape_new(x, mpc_escape_input_raw_cchar, mpc_escape_output_raw_cchar);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_unescape_char_raw(mpc_val_t *x) {
   mpc_val_t *y = mpcf_unescape_new(x, mpc_escape_input_raw_cchar, mpc_escape_output_raw_cchar);
   free(x);
   return y;
 }
 
 mpc_val_t *mpcf_null(int n, mpc_val_t** xs) { (void) n; (void) xs; return NULL; }
 mpc_val_t *mpcf_fst(int n, mpc_val_t **xs) { (void) n; return xs[0]; }
 mpc_val_t *mpcf_snd(int n, mpc_val_t **xs) { (void) n; return xs[1]; }
 mpc_val_t *mpcf_trd(int n, mpc_val_t **xs) { (void) n; return xs[2]; }
 
 static mpc_val_t *mpcf_nth_free(int n, mpc_val_t **xs, int x) {
   int i;
   for (i = 0; i < n; i++) {
     if (i != x) { free(xs[i]); }
   }
   return xs[x];
 }
 
 mpc_val_t *mpcf_fst_free(int n, mpc_val_t **xs) { return mpcf_nth_free(n, xs, 0); }
 mpc_val_t *mpcf_snd_free(int n, mpc_val_t **xs) { return mpcf_nth_free(n, xs, 1); }
 mpc_val_t *mpcf_trd_free(int n, mpc_val_t **xs) { return mpcf_nth_free(n, xs, 2); }
 mpc_val_t *mpcf_all_free(int n, mpc_val_t** xs) {
   int i;
   for (i = 0; i < n; i++) {
     free(xs[i]);
   }
   return NULL;
 }
 
 mpc_val_t *mpcf_strfold(int n, mpc_val_t **xs) {
   int i;
   size_t l = 0;
 
   if (n == 0) { return calloc(1, 1); }
 
   for (i = 0; i < n; i++) { l += strlen(xs[i]); }
 
   xs[0] = realloc(xs[0], l + 1);
 
   for (i = 1; i < n; i++) {
     strcat(xs[0], xs[i]); free(xs[i]);
   }
 
   return xs[0];
 }
 
 /*
 ** Printing
 */
 
 static void mpc_print_unretained(mpc_parser_t *p, int force) {
 
   /* TODO: Print Everything Escaped */
 
   int i;
   char *s, *e;
   char buff[2];
 
   if (p->retained && !force) {;
     if (p->name) { printf("<%s>", p->name); }
     else { printf("<anon>"); }
     return;
   }
 
   if (p->type == MPC_TYPE_UNDEFINED) { printf("<?>"); }
   if (p->type == MPC_TYPE_PASS)   { printf("<:>"); }
   if (p->type == MPC_TYPE_FAIL)   { printf("<!>"); }
   if (p->type == MPC_TYPE_LIFT)   { printf("<#>"); }
   if (p->type == MPC_TYPE_STATE)  { printf("<S>"); }
   if (p->type == MPC_TYPE_ANCHOR) { printf("<@>"); }
   if (p->type == MPC_TYPE_EXPECT) {
     printf("%s", p->data.expect.m);
     /*mpc_print_unretained(p->data.expect.x, 0);*/
   }
 
   if (p->type == MPC_TYPE_ANY) { printf("<.>"); }
   if (p->type == MPC_TYPE_SATISFY) { printf("<f>"); }
 
   if (p->type == MPC_TYPE_SINGLE) {
     buff[0] = p->data.single.x; buff[1] = '\0';
     s = mpcf_escape_new(
       buff,
       mpc_escape_input_c,
       mpc_escape_output_c);
     printf("'%s'", s);
     free(s);
   }
 
   if (p->type == MPC_TYPE_RANGE) {
     buff[0] = p->data.range.x; buff[1] = '\0';
     s = mpcf_escape_new(
       buff,
       mpc_escape_input_c,
       mpc_escape_output_c);
     buff[0] = p->data.range.y; buff[1] = '\0';
     e = mpcf_escape_new(
       buff,
       mpc_escape_input_c,
       mpc_escape_output_c);
     printf("[%s-%s]", s, e);
     free(s);
     free(e);
   }
 
   if (p->type == MPC_TYPE_ONEOF) {
     s = mpcf_escape_new(
       p->data.string.x,
       mpc_escape_input_c,
       mpc_escape_output_c);
     printf("[%s]", s);
     free(s);
   }
 
   if (p->type == MPC_TYPE_NONEOF) {
     s = mpcf_escape_new(
       p->data.string.x,
       mpc_escape_input_c,
       mpc_escape_output_c);
     printf("[^%s]", s);
     free(s);
   }
 
   if (p->type == MPC_TYPE_STRING) {
     s = mpcf_escape_new(
       p->data.string.x,
       mpc_escape_input_c,
       mpc_escape_output_c);
     printf("\"%s\"", s);
     free(s);
   }
 
   if (p->type == MPC_TYPE_APPLY)    { mpc_print_unretained(p->data.apply.x, 0); }
   if (p->type == MPC_TYPE_APPLY_TO) { mpc_print_unretained(p->data.apply_to.x, 0); }
   if (p->type == MPC_TYPE_PREDICT)  { mpc_print_unretained(p->data.predict.x, 0); }
 
   if (p->type == MPC_TYPE_NOT)   { mpc_print_unretained(p->data.not.x, 0); printf("!"); }
   if (p->type == MPC_TYPE_MAYBE) { mpc_print_unretained(p->data.not.x, 0); printf("?"); }
 
   if (p->type == MPC_TYPE_MANY)  { mpc_print_unretained(p->data.repeat.x, 0); printf("*"); }
   if (p->type == MPC_TYPE_MANY1) { mpc_print_unretained(p->data.repeat.x, 0); printf("+"); }
   if (p->type == MPC_TYPE_COUNT) { mpc_print_unretained(p->data.repeat.x, 0); printf("{%i}", p->data.repeat.n); }
 
   if (p->type == MPC_TYPE_OR) {
     printf("(");
     for(i = 0; i < p->data.or.n-1; i++) {
       mpc_print_unretained(p->data.or.xs[i], 0);
       printf(" | ");
     }
     mpc_print_unretained(p->data.or.xs[p->data.or.n-1], 0);
     printf(")");
   }
 
   if (p->type == MPC_TYPE_AND) {
     printf("(");
     for(i = 0; i < p->data.and.n-1; i++) {
       mpc_print_unretained(p->data.and.xs[i], 0);
       printf(" ");
     }
     mpc_print_unretained(p->data.and.xs[p->data.and.n-1], 0);
     printf(")");
   }
 
   if (p->type == MPC_TYPE_CHECK) {
     mpc_print_unretained(p->data.check.x, 0);
     printf("->?");
   }
   if (p->type == MPC_TYPE_CHECK_WITH) {
     mpc_print_unretained(p->data.check_with.x, 0);
     printf("->?");
   }
 
 }
 
 void mpc_print(mpc_parser_t *p) {
   mpc_print_unretained(p, 1);
   printf("\n");
 }
 
 /*
 ** Testing
 */
 
 /*
 ** These functions are slightly unwieldy and
 ** also the whole of the testing suite for mpc
 ** mpc is pretty shaky.
 **
 ** It could do with a lot more tests and more
 ** precision. Currently I am only really testing
 ** changes off of the examples.
 **
 */
 
 int mpc_test_fail(mpc_parser_t *p, const char *s, const void *d,
   int(*tester)(const void*, const void*),
   mpc_dtor_t destructor,
   void(*printer)(const void*)) {
   mpc_result_t r;
   (void) printer;
   if (mpc_parse("<test>", s, p, &r)) {
 
     if (tester(r.output, d)) {
       destructor(r.output);
       return 0;
     } else {
       destructor(r.output);
       return 1;
     }
 
   } else {
     mpc_err_delete(r.error);
     return 1;
   }
 
 }
 
 int mpc_test_pass(mpc_parser_t *p, const char *s, const void *d,
   int(*tester)(const void*, const void*),
   mpc_dtor_t destructor,
   void(*printer)(const void*)) {
 
   mpc_result_t r;
   if (mpc_parse("<test>", s, p, &r)) {
 
     if (tester(r.output, d)) {
       destructor(r.output);
       return 1;
     } else {
       printf("Got "); printer(r.output); printf("\n");
       printf("Expected "); printer(d); printf("\n");
       destructor(r.output);
       return 0;
     }
 
   } else {
     mpc_err_print(r.error);
     mpc_err_delete(r.error);
     return 0;
 
   }
 
 }
 
 
 /*
 ** AST
 */
 
 void mpc_ast_delete(mpc_ast_t *a) {
 
   int i;
 
   if (a == NULL) { return; }
 
   for (i = 0; i < a->children_num; i++) {
     mpc_ast_delete(a->children[i]);
   }
 
   free(a->children);
   free(a->tag);
   free(a->contents);
   free(a);
 
 }
 
 static void mpc_ast_delete_no_children(mpc_ast_t *a) {
   free(a->children);
   free(a->tag);
   free(a->contents);
   free(a);
 }
 
 mpc_ast_t *mpc_ast_new(const char *tag, const char *contents) {
 
   mpc_ast_t *a = malloc(sizeof(mpc_ast_t));
 
   a->tag = malloc(strlen(tag) + 1);
   strcpy(a->tag, tag);
 
   a->contents = malloc(strlen(contents) + 1);
   strcpy(a->contents, contents);
 
   a->state = mpc_state_new();
 
   a->children_num = 0;
   a->children = NULL;
   return a;
 
 }
 
 mpc_ast_t *mpc_ast_build(int n, const char *tag, ...) {
 
   mpc_ast_t *a = mpc_ast_new(tag, "");
 
   int i;
   va_list va;
   va_start(va, tag);
 
   for (i = 0; i < n; i++) {
     mpc_ast_add_child(a, va_arg(va, mpc_ast_t*));
   }
 
   va_end(va);
 
   return a;
 
 }
 
 mpc_ast_t *mpc_ast_add_root(mpc_ast_t *a) {
 
   mpc_ast_t *r;
 
   if (a == NULL) { return a; }
   if (a->children_num == 0) { return a; }
   if (a->children_num == 1) { return a; }
 
   r = mpc_ast_new(">", "");
   mpc_ast_add_child(r, a);
   return r;
 }
 
 int mpc_ast_eq(mpc_ast_t *a, mpc_ast_t *b) {
 
   int i;
 
   if (strcmp(a->tag, b->tag) != 0) { return 0; }
   if (strcmp(a->contents, b->contents) != 0) { return 0; }
   if (a->children_num != b->children_num) { return 0; }
 
   for (i = 0; i < a->children_num; i++) {
     if (!mpc_ast_eq(a->children[i], b->children[i])) { return 0; }
   }
 
   return 1;
 }
 
 mpc_ast_t *mpc_ast_add_child(mpc_ast_t *r, mpc_ast_t *a) {
   r->children_num++;
   r->children = realloc(r->children, sizeof(mpc_ast_t*) * r->children_num);
   r->children[r->children_num-1] = a;
   return r;
 }
 
 mpc_ast_t *mpc_ast_add_tag(mpc_ast_t *a, const char *t) {
   if (a == NULL) { return a; }
   a->tag = realloc(a->tag, strlen(t) + 1 + strlen(a->tag) + 1);
   memmove(a->tag + strlen(t) + 1, a->tag, strlen(a->tag)+1);
   memmove(a->tag, t, strlen(t));
   memmove(a->tag + strlen(t), "|", 1);
   return a;
 }
 
 mpc_ast_t *mpc_ast_add_root_tag(mpc_ast_t *a, const char *t) {
   if (a == NULL) { return a; }
   a->tag = realloc(a->tag, (strlen(t)-1) + strlen(a->tag) + 1);
   memmove(a->tag + (strlen(t)-1), a->tag, strlen(a->tag)+1);
   memmove(a->tag, t, (strlen(t)-1));
   return a;
 }
 
 mpc_ast_t *mpc_ast_tag(mpc_ast_t *a, const char *t) {
   a->tag = realloc(a->tag, strlen(t) + 1);
   strcpy(a->tag, t);
   return a;
 }
 
 mpc_ast_t *mpc_ast_state(mpc_ast_t *a, mpc_state_t s) {
   if (a == NULL) { return a; }
   a->state = s;
   return a;
 }
 
 static void mpc_ast_print_depth(mpc_ast_t *a, int d, FILE *fp) {
 
   int i;
 
   if (a == NULL) {
     fprintf(fp, "NULL\n");
     return;
   }
 
   for (i = 0; i < d; i++) { fprintf(fp, "  "); }
 
   if (strlen(a->contents)) {
     fprintf(fp, "%s:%lu:%lu '%s'\n", a->tag,
       (long unsigned int)(a->state.row+1),
       (long unsigned int)(a->state.col+1),
       a->contents);
   } else {
     fprintf(fp, "%s \n", a->tag);
   }
 
   for (i = 0; i < a->children_num; i++) {
     mpc_ast_print_depth(a->children[i], d+1, fp);
   }
 
 }
 
 void mpc_ast_print(mpc_ast_t *a) {
   mpc_ast_print_depth(a, 0, stdout);
 }
 
 void mpc_ast_print_to(mpc_ast_t *a, FILE *fp) {
   mpc_ast_print_depth(a, 0, fp);
 }
 
 int mpc_ast_get_index(mpc_ast_t *ast, const char *tag) {
   return mpc_ast_get_index_lb(ast, tag, 0);
 }
 
 int mpc_ast_get_index_lb(mpc_ast_t *ast, const char *tag, int lb) {
   int i;
 
   for(i=lb; i<ast->children_num; i++) {
     if(strcmp(ast->children[i]->tag, tag) == 0) {
       return i;
     }
   }
 
   return -1;
 }
 
 mpc_ast_t *mpc_ast_get_child(mpc_ast_t *ast, const char *tag) {
   return mpc_ast_get_child_lb(ast, tag, 0);
 }
 
 mpc_ast_t *mpc_ast_get_child_lb(mpc_ast_t *ast, const char *tag, int lb) {
   int i;
 
   for(i=lb; i<ast->children_num; i++) {
     if(strcmp(ast->children[i]->tag, tag) == 0) {
       return ast->children[i];
     }
   }
 
   return NULL;
 }
 
 mpc_ast_trav_t *mpc_ast_traverse_start(mpc_ast_t *ast,
                                        mpc_ast_trav_order_t order)
 {
   mpc_ast_trav_t *trav, *n_trav;
   mpc_ast_t *cnode = ast;
 
   /* Create the traversal structure */
   trav = malloc(sizeof(mpc_ast_trav_t));
   trav->curr_node = cnode;
   trav->parent = NULL;
   trav->curr_child = 0;
   trav->order = order;
 
   /* Get start node */
   switch(order) {
     case mpc_ast_trav_order_pre:
       /* Nothing else is needed for pre order start */
       break;
 
     case mpc_ast_trav_order_post:
       while(cnode->children_num > 0) {
         cnode = cnode->children[0];
 
         n_trav = malloc(sizeof(mpc_ast_trav_t));
         n_trav->curr_node = cnode;
         n_trav->parent = trav;
         n_trav->curr_child = 0;
         n_trav->order = order;
 
         trav = n_trav;
       }
 
       break;
 
     default:
       /* Unreachable, but compiler complaints */
       break;
   }
 
   return trav;
 }
 
 mpc_ast_t *mpc_ast_traverse_next(mpc_ast_trav_t **trav) {
   mpc_ast_trav_t *n_trav, *to_free;
   mpc_ast_t *ret = NULL;
   int cchild;
 
   /* The end of traversal was reached */
   if(*trav == NULL) return NULL;
 
   switch((*trav)->order) {
     case mpc_ast_trav_order_pre:
       ret = (*trav)->curr_node;
 
       /* If there aren't any more children, go up */
       while(*trav != NULL &&
         (*trav)->curr_child >= (*trav)->curr_node->children_num)
       {
         to_free = *trav;
         *trav = (*trav)->parent;
         free(to_free);
       }
 
       /* If trav is NULL, the end was reached */
       if(*trav == NULL) {
         break;
       }
 
       /* Go to next child */
       n_trav = malloc(sizeof(mpc_ast_trav_t));
 
       cchild = (*trav)->curr_child;
       n_trav->curr_node = (*trav)->curr_node->children[cchild];
       n_trav->parent = *trav;
       n_trav->curr_child = 0;
       n_trav->order = (*trav)->order;
 
       (*trav)->curr_child++;
       *trav = n_trav;
 
       break;
 
     case mpc_ast_trav_order_post:
       ret = (*trav)->curr_node;
 
       /* Move up tree to the parent If the parent doesn't have any more nodes,
        * then this is the current node. If it does, move down to its left most
        * child. Also, free the previous traversal node */
       to_free = *trav;
       *trav = (*trav)->parent;
       free(to_free);
 
       if(*trav == NULL)
         break;
 
       /* Next child */
       (*trav)->curr_child++;
 
       /* If there aren't any more children, this is the next node */
       if((*trav)->curr_child >= (*trav)->curr_node->children_num) {
         break;
       }
 
       /* If there are still more children, find the leftmost child from this
        * node */
       while((*trav)->curr_node->children_num > 0) {
         n_trav = malloc(sizeof(mpc_ast_trav_t));
 
         cchild = (*trav)->curr_child;
         n_trav->curr_node = (*trav)->curr_node->children[cchild];
         n_trav->parent = *trav;
         n_trav->curr_child = 0;
         n_trav->order = (*trav)->order;
 
         *trav = n_trav;
       }
 
     default:
       /* Unreachable, but compiler complaints */
       break;
   }
 
   return ret;
 }
 
 void mpc_ast_traverse_free(mpc_ast_trav_t **trav) {
   mpc_ast_trav_t *n_trav;
 
   /* Go through parents until all are free */
   while(*trav != NULL) {
       n_trav = (*trav)->parent;
       free(*trav);
       *trav = n_trav;
   }
 }
 
 mpc_val_t *mpcf_fold_ast(int n, mpc_val_t **xs) {
 
   int i, j;
   mpc_ast_t** as = (mpc_ast_t**)xs;
   mpc_ast_t *r;
 
   if (n == 0) { return NULL; }
   if (n == 1) { return xs[0]; }
   if (n == 2 && xs[1] == NULL) { return xs[0]; }
   if (n == 2 && xs[0] == NULL) { return xs[1]; }
 
   r = mpc_ast_new(">", "");
 
   for (i = 0; i < n; i++) {
 
     if (as[i] == NULL) { continue; }
 
     if        (as[i] && as[i]->children_num == 0) {
       mpc_ast_add_child(r, as[i]);
     } else if (as[i] && as[i]->children_num == 1) {
       mpc_ast_add_child(r, mpc_ast_add_root_tag(as[i]->children[0], as[i]->tag));
       mpc_ast_delete_no_children(as[i]);
     } else if (as[i] && as[i]->children_num >= 2) {
       for (j = 0; j < as[i]->children_num; j++) {
         mpc_ast_add_child(r, as[i]->children[j]);
       }
       mpc_ast_delete_no_children(as[i]);
     }
 
   }
 
   if (r->children_num) {
     r->state = r->children[0]->state;
   }
 
   return r;
 }
 
 mpc_val_t *mpcf_str_ast(mpc_val_t *c) {
   mpc_ast_t *a = mpc_ast_new("", c);
   free(c);
   return a;
 }
 
 mpc_val_t *mpcf_state_ast(int n, mpc_val_t **xs) {
   mpc_state_t *s = ((mpc_state_t**)xs)[0];
   mpc_ast_t *a = ((mpc_ast_t**)xs)[1];
   (void)n;
   a = mpc_ast_state(a, *s);
   free(s);
   return a;
 }
 
 mpc_parser_t *mpca_state(mpc_parser_t *a) {
   return mpc_and(2, mpcf_state_ast, mpc_state(), a, free);
 }
 
 mpc_parser_t *mpca_tag(mpc_parser_t *a, const char *t) {
   return mpc_apply_to(a, (mpc_apply_to_t)mpc_ast_tag, (void*)t);
 }
 
 mpc_parser_t *mpca_add_tag(mpc_parser_t *a, const char *t) {
   return mpc_apply_to(a, (mpc_apply_to_t)mpc_ast_add_tag, (void*)t);
 }
 
 mpc_parser_t *mpca_root(mpc_parser_t *a) {
   return mpc_apply(a, (mpc_apply_t)mpc_ast_add_root);
 }
 
 mpc_parser_t *mpca_not(mpc_parser_t *a) { return mpc_not(a, (mpc_dtor_t)mpc_ast_delete); }
 mpc_parser_t *mpca_maybe(mpc_parser_t *a) { return mpc_maybe(a); }
 mpc_parser_t *mpca_many(mpc_parser_t *a) { return mpc_many(mpcf_fold_ast, a); }
 mpc_parser_t *mpca_many1(mpc_parser_t *a) { return mpc_many1(mpcf_fold_ast, a); }
 mpc_parser_t *mpca_count(int n, mpc_parser_t *a) { return mpc_count(n, mpcf_fold_ast, a, (mpc_dtor_t)mpc_ast_delete); }
 
 mpc_parser_t *mpca_or(int n, ...) {
 
   int i;
   va_list va;
 
   mpc_parser_t *p = mpc_undefined();
 
   p->type = MPC_TYPE_OR;
   p->data.or.n = n;
   p->data.or.xs = malloc(sizeof(mpc_parser_t*) * n);
 
   va_start(va, n);
   for (i = 0; i < n; i++) {
     p->data.or.xs[i] = va_arg(va, mpc_parser_t*);
   }
   va_end(va);
 
   return p;
 
 }
 
 mpc_parser_t *mpca_and(int n, ...) {
 
   int i;
   va_list va;
 
   mpc_parser_t *p = mpc_undefined();
 
   p->type = MPC_TYPE_AND;
   p->data.and.n = n;
   p->data.and.f = mpcf_fold_ast;
   p->data.and.xs = malloc(sizeof(mpc_parser_t*) * n);
   p->data.and.dxs = malloc(sizeof(mpc_dtor_t) * (n-1));
 
   va_start(va, n);
   for (i = 0; i < n; i++) {
     p->data.and.xs[i] = va_arg(va, mpc_parser_t*);
   }
   for (i = 0; i < (n-1); i++) {
     p->data.and.dxs[i] = (mpc_dtor_t)mpc_ast_delete;
   }
   va_end(va);
 
   return p;
 }
 
 mpc_parser_t *mpca_total(mpc_parser_t *a) { return mpc_total(a, (mpc_dtor_t)mpc_ast_delete); }
 
 /*
 ** Grammar Parser
 */
 
 /*
 ** This is another interesting bootstrapping.
 **
 ** Having a general purpose AST type allows
 ** users to specify the grammar alone and
 ** let all fold rules be automatically taken
 ** care of by existing functions.
 **
 ** You don't get to control the type spat
 ** out but this means you can make a nice
 ** parser to take in some grammar in nice
 ** syntax and spit out a parser that works.
 **
 ** The grammar for this looks surprisingly
 ** like regex but the main difference is that
 ** it is now whitespace insensitive and the
 ** base type takes literals of some form.
 */
 
 /*
 **
 **  ### Grammar Grammar
 **
 **      <grammar> : (<term> "|" <grammar>) | <term>
 **
 **      <term> : <factor>*
 **
 **      <factor> : <base>
 **               | <base> "*"
 **               | <base> "+"
 **               | <base> "?"
 **               | <base> "{" <digits> "}"
 **
 **      <base> : "<" (<digits> | <ident>) ">"
 **             | <string_lit>
 **             | <char_lit>
 **             | <regex_lit> <regex_mode>
 **             | "(" <grammar> ")"
 */
 
 typedef struct {
   va_list *va;
   int parsers_num;
   mpc_parser_t **parsers;
   int flags;
 } mpca_grammar_st_t;
 
 static mpc_val_t *mpcaf_grammar_or(int n, mpc_val_t **xs) {
   (void) n;
   if (xs[1] == NULL) { return xs[0]; }
   else { return mpca_or(2, xs[0], xs[1]); }
 }
 
 static mpc_val_t *mpcaf_grammar_and(int n, mpc_val_t **xs) {
   int i;
   mpc_parser_t *p = mpc_pass();
   for (i = 0; i < n; i++) {
     if (xs[i] != NULL) { p = mpca_and(2, p, xs[i]); }
   }
   return p;
 }
 
 static mpc_val_t *mpcaf_grammar_repeat(int n, mpc_val_t **xs) {
   int num;
   (void) n;
   if (xs[1] == NULL) { return xs[0]; }
   switch(((char*)xs[1])[0])
   {
     case '*': { free(xs[1]); return mpca_many(xs[0]); }; break;
     case '+': { free(xs[1]); return mpca_many1(xs[0]); }; break;
     case '?': { free(xs[1]); return mpca_maybe(xs[0]); }; break;
     case '!': { free(xs[1]); return mpca_not(xs[0]); }; break;
     default:
       num = *((int*)xs[1]);
       free(xs[1]);
   }
   return mpca_count(num, xs[0]);
 }
 
 static mpc_val_t *mpcaf_grammar_string(mpc_val_t *x, void *s) {
   mpca_grammar_st_t *st = s;
   char *y = mpcf_unescape(x);
   mpc_parser_t *p = (st->flags & MPCA_LANG_WHITESPACE_SENSITIVE) ? mpc_string(y) : mpc_tok(mpc_string(y));
   free(y);
   return mpca_state(mpca_tag(mpc_apply(p, mpcf_str_ast), "string"));
 }
 
 static mpc_val_t *mpcaf_grammar_char(mpc_val_t *x, void *s) {
   mpca_grammar_st_t *st = s;
   char *y = mpcf_unescape(x);
   mpc_parser_t *p = (st->flags & MPCA_LANG_WHITESPACE_SENSITIVE) ? mpc_char(y[0]) : mpc_tok(mpc_char(y[0]));
   free(y);
   return mpca_state(mpca_tag(mpc_apply(p, mpcf_str_ast), "char"));
 }
 
 static mpc_val_t *mpcaf_fold_regex(int n, mpc_val_t **xs) {
   char *y = xs[0];
   char *m = xs[1];
   mpca_grammar_st_t *st = xs[2];
   mpc_parser_t *p;
   int mode = MPC_RE_DEFAULT;
 
   (void)n;
   if (strchr(m, 'm')) { mode |= MPC_RE_MULTILINE; }
   if (strchr(m, 's')) { mode |= MPC_RE_DOTALL; }
   y = mpcf_unescape_regex(y);
   p = (st->flags & MPCA_LANG_WHITESPACE_SENSITIVE) ? mpc_re_mode(y, mode) : mpc_tok(mpc_re_mode(y, mode));
   free(y);
   free(m);
 
   return mpca_state(mpca_tag(mpc_apply(p, mpcf_str_ast), "regex"));
 }
 
 /* Should this just use `isdigit` instead? */
 static int is_number(const char* s) {
   size_t i;
   for (i = 0; i < strlen(s); i++) { if (!strchr("0123456789", s[i])) { return 0; } }
   return 1;
 }
 
 static mpc_parser_t *mpca_grammar_find_parser(char *x, mpca_grammar_st_t *st) {
 
   int i;
   mpc_parser_t *p;
 
   /* Case of Number */
   if (is_number(x)) {
 
     i = strtol(x, NULL, 10);
 
     while (st->parsers_num <= i) {
       st->parsers_num++;
       st->parsers = realloc(st->parsers, sizeof(mpc_parser_t*) * st->parsers_num);
       st->parsers[st->parsers_num-1] = va_arg(*st->va, mpc_parser_t*);
       if (st->parsers[st->parsers_num-1] == NULL) {
         return mpc_failf("No Parser in position %i! Only supplied %i Parsers!", i, st->parsers_num);
       }
     }
 
     return st->parsers[st->parsers_num-1];
 
   /* Case of Identifier */
   } else {
 
     /* Search Existing Parsers */
     for (i = 0; i < st->parsers_num; i++) {
       mpc_parser_t *q = st->parsers[i];
       if (q == NULL) { return mpc_failf("Unknown Parser '%s'!", x); }
       if (q->name && strcmp(q->name, x) == 0) { return q; }
     }
 
     /* Search New Parsers */
     while (1) {
 
       p = va_arg(*st->va, mpc_parser_t*);
 
       st->parsers_num++;
       st->parsers = realloc(st->parsers, sizeof(mpc_parser_t*) * st->parsers_num);
       st->parsers[st->parsers_num-1] = p;
 
       if (p == NULL || p->name == NULL) { return mpc_failf("Unknown Parser '%s'!", x); }
       if (p->name && strcmp(p->name, x) == 0) { return p; }
 
     }
 
   }
 
 }
 
 static mpc_val_t *mpcaf_grammar_id(mpc_val_t *x, void *s) {
 
   mpca_grammar_st_t *st = s;
   mpc_parser_t *p = mpca_grammar_find_parser(x, st);
   free(x);
 
   if (p->name) {
     return mpca_state(mpca_root(mpca_add_tag(p, p->name)));
   } else {
     return mpca_state(mpca_root(p));
   }
 }
 
 mpc_parser_t *mpca_grammar_st(const char *grammar, mpca_grammar_st_t *st) {
 
   char *err_msg;
   mpc_parser_t *err_out;
   mpc_result_t r;
   mpc_parser_t *GrammarTotal, *Grammar, *Term, *Factor, *Base;
 
   GrammarTotal = mpc_new("grammar_total");
   Grammar = mpc_new("grammar");
   Term = mpc_new("term");
   Factor = mpc_new("factor");
   Base = mpc_new("base");
 
   mpc_define(GrammarTotal,
     mpc_predictive(mpc_total(Grammar, mpc_soft_delete))
   );
 
   mpc_define(Grammar, mpc_and(2, mpcaf_grammar_or,
     Term,
     mpc_maybe(mpc_and(2, mpcf_snd_free, mpc_sym("|"), Grammar, free)),
     mpc_soft_delete
   ));
 
   mpc_define(Term, mpc_many1(mpcaf_grammar_and, Factor));
 
   mpc_define(Factor, mpc_and(2, mpcaf_grammar_repeat,
     Base,
       mpc_or(6,
         mpc_sym("*"),
         mpc_sym("+"),
         mpc_sym("?"),
         mpc_sym("!"),
         mpc_tok_brackets(mpc_int(), free),
         mpc_pass()),
     mpc_soft_delete
   ));
 
   mpc_define(Base, mpc_or(5,
     mpc_apply_to(mpc_tok(mpc_string_lit()), mpcaf_grammar_string, st),
     mpc_apply_to(mpc_tok(mpc_char_lit()),   mpcaf_grammar_char, st),
     mpc_tok(mpc_and(3, mpcaf_fold_regex, mpc_regex_lit(), mpc_many(mpcf_strfold, mpc_oneof("ms")), mpc_lift_val(st), free, free)),
     mpc_apply_to(mpc_tok_braces(mpc_or(2, mpc_digits(), mpc_ident()), free), mpcaf_grammar_id, st),
     mpc_tok_parens(Grammar, mpc_soft_delete)
   ));
 
   mpc_optimise(GrammarTotal);
   mpc_optimise(Grammar);
   mpc_optimise(Factor);
   mpc_optimise(Term);
   mpc_optimise(Base);
 
   if(!mpc_parse("<mpc_grammar_compiler>", grammar, GrammarTotal, &r)) {
     err_msg = mpc_err_string(r.error);
     err_out = mpc_failf("Invalid Grammar: %s", err_msg);
     mpc_err_delete(r.error);
     free(err_msg);
     r.output = err_out;
   }
 
   mpc_cleanup(5, GrammarTotal, Grammar, Term, Factor, Base);
 
   mpc_optimise(r.output);
 
   return (st->flags & MPCA_LANG_PREDICTIVE) ? mpc_predictive(r.output) : r.output;
 
 }
 
 mpc_parser_t *mpca_grammar(int flags, const char *grammar, ...) {
   mpca_grammar_st_t st;
   mpc_parser_t *res;
   va_list va;
   va_start(va, grammar);
 
   st.va = &va;
   st.parsers_num = 0;
   st.parsers = NULL;
   st.flags = flags;
 
   res = mpca_grammar_st(grammar, &st);
   free(st.parsers);
   va_end(va);
   return res;
 }
 
 typedef struct {
   char *ident;
   char *name;
   mpc_parser_t *grammar;
 } mpca_stmt_t;
 
 static mpc_val_t *mpca_stmt_afold(int n, mpc_val_t **xs) {
   mpca_stmt_t *stmt = malloc(sizeof(mpca_stmt_t));
   stmt->ident = ((char**)xs)[0];
   stmt->name = ((char**)xs)[1];
   stmt->grammar = ((mpc_parser_t**)xs)[3];
   (void) n;
   free(((char**)xs)[2]);
   free(((char**)xs)[4]);
 
   return stmt;
 }
 
 static mpc_val_t *mpca_stmt_fold(int n, mpc_val_t **xs) {
 
   int i;
   mpca_stmt_t **stmts = malloc(sizeof(mpca_stmt_t*) * (n+1));
 
   for (i = 0; i < n; i++) {
     stmts[i] = xs[i];
   }
   stmts[n] = NULL;
 
   return stmts;
 }
 
 static void mpca_stmt_list_delete(mpc_val_t *x) {
 
   mpca_stmt_t **stmts = x;
 
   while(*stmts) {
     mpca_stmt_t *stmt = *stmts;
     free(stmt->ident);
     free(stmt->name);
     mpc_soft_delete(stmt->grammar);
     free(stmt);
     stmts++;
   }
   free(x);
 
 }
 
 static mpc_val_t *mpca_stmt_list_apply_to(mpc_val_t *x, void *s) {
 
   mpca_grammar_st_t *st = s;
   mpca_stmt_t *stmt;
   mpca_stmt_t **stmts = x;
   mpc_parser_t *left;
 
   while(*stmts) {
     stmt = *stmts;
     left = mpca_grammar_find_parser(stmt->ident, st);
     if (st->flags & MPCA_LANG_PREDICTIVE) { stmt->grammar = mpc_predictive(stmt->grammar); }
     if (stmt->name) { stmt->grammar = mpc_expect(stmt->grammar, stmt->name); }
     mpc_optimise(stmt->grammar);
     mpc_define(left, stmt->grammar);
     free(stmt->ident);
     free(stmt->name);
     free(stmt);
     stmts++;
   }
 
   free(x);
 
   return NULL;
 }
 
 static mpc_err_t *mpca_lang_st(mpc_input_t *i, mpca_grammar_st_t *st) {
 
   mpc_result_t r;
   mpc_err_t *e;
   mpc_parser_t *Lang, *Stmt, *Grammar, *Term, *Factor, *Base;
 
   Lang    = mpc_new("lang");
   Stmt    = mpc_new("stmt");
   Grammar = mpc_new("grammar");
   Term    = mpc_new("term");
   Factor  = mpc_new("factor");
   Base    = mpc_new("base");
 
   mpc_define(Lang, mpc_apply_to(
     mpc_total(mpc_predictive(mpc_many(mpca_stmt_fold, Stmt)), mpca_stmt_list_delete),
     mpca_stmt_list_apply_to, st
   ));
 
   mpc_define(Stmt, mpc_and(5, mpca_stmt_afold,
     mpc_tok(mpc_ident()), mpc_maybe(mpc_tok(mpc_string_lit())), mpc_sym(":"), Grammar, mpc_sym(";"),
     free, free, free, mpc_soft_delete
   ));
 
   mpc_define(Grammar, mpc_and(2, mpcaf_grammar_or,
       Term,
       mpc_maybe(mpc_and(2, mpcf_snd_free, mpc_sym("|"), Grammar, free)),
       mpc_soft_delete
   ));
 
   mpc_define(Term, mpc_many1(mpcaf_grammar_and, Factor));
 
   mpc_define(Factor, mpc_and(2, mpcaf_grammar_repeat,
     Base,
       mpc_or(6,
         mpc_sym("*"),
         mpc_sym("+"),
         mpc_sym("?"),
         mpc_sym("!"),
         mpc_tok_brackets(mpc_int(), free),
         mpc_pass()),
     mpc_soft_delete
   ));
 
   mpc_define(Base, mpc_or(5,
     mpc_apply_to(mpc_tok(mpc_string_lit()), mpcaf_grammar_string, st),
     mpc_apply_to(mpc_tok(mpc_char_lit()),   mpcaf_grammar_char, st),
     mpc_tok(mpc_and(3, mpcaf_fold_regex, mpc_regex_lit(), mpc_many(mpcf_strfold, mpc_oneof("ms")), mpc_lift_val(st), free, free)),
     mpc_apply_to(mpc_tok_braces(mpc_or(2, mpc_digits(), mpc_ident()), free), mpcaf_grammar_id, st),
     mpc_tok_parens(Grammar, mpc_soft_delete)
   ));
 
   mpc_optimise(Lang);
   mpc_optimise(Stmt);
   mpc_optimise(Grammar);
   mpc_optimise(Term);
   mpc_optimise(Factor);
   mpc_optimise(Base);
 
   if (!mpc_parse_input(i, Lang, &r)) {
     e = r.error;
   } else {
     e = NULL;
   }
 
   mpc_cleanup(6, Lang, Stmt, Grammar, Term, Factor, Base);
 
   return e;
 }
 
 mpc_err_t *mpca_lang_file(int flags, FILE *f, ...) {
   mpca_grammar_st_t st;
   mpc_input_t *i;
   mpc_err_t *err;
 
   va_list va;
   va_start(va, f);
 
   st.va = &va;
   st.parsers_num = 0;
   st.parsers = NULL;
   st.flags = flags;
 
   i = mpc_input_new_file("<mpca_lang_file>", f);
   err = mpca_lang_st(i, &st);
   mpc_input_delete(i);
 
   free(st.parsers);
   va_end(va);
   return err;
 }
 
 mpc_err_t *mpca_lang_pipe(int flags, FILE *p, ...) {
   mpca_grammar_st_t st;
   mpc_input_t *i;
   mpc_err_t *err;
 
   va_list va;
   va_start(va, p);
 
   st.va = &va;
   st.parsers_num = 0;
   st.parsers = NULL;
   st.flags = flags;
 
   i = mpc_input_new_pipe("<mpca_lang_pipe>", p);
   err = mpca_lang_st(i, &st);
   mpc_input_delete(i);
 
   free(st.parsers);
   va_end(va);
   return err;
 }
 
 mpc_err_t *mpca_lang(int flags, const char *language, ...) {
 
   mpca_grammar_st_t st;
   mpc_input_t *i;
   mpc_err_t *err;
 
   va_list va;
   va_start(va, language);
 
   st.va = &va;
   st.parsers_num = 0;
   st.parsers = NULL;
   st.flags = flags;
 
   i = mpc_input_new_string("<mpca_lang>", language);
   err = mpca_lang_st(i, &st);
   mpc_input_delete(i);
 
   free(st.parsers);
   va_end(va);
   return err;
 }
 
 mpc_err_t *mpca_lang_contents(int flags, const char *filename, ...) {
 
   mpca_grammar_st_t st;
   mpc_input_t *i;
   mpc_err_t *err;
 
   va_list va;
 
   FILE *f = fopen(filename, "rb");
 
   if (f == NULL) {
     err = mpc_err_file(filename, "Unable to open file!");
     return err;
   }
 
   va_start(va, filename);
 
   st.va = &va;
   st.parsers_num = 0;
   st.parsers = NULL;
   st.flags = flags;
 
   i = mpc_input_new_file(filename, f);
   err = mpca_lang_st(i, &st);
   mpc_input_delete(i);
 
   free(st.parsers);
   va_end(va);
 
   fclose(f);
 
   return err;
 }
 
 static int mpc_nodecount_unretained(mpc_parser_t* p, int force) {
 
   int i, total;
 
   if (p->retained && !force) { return 0; }
 
   if (p->type == MPC_TYPE_EXPECT) { return 1 + mpc_nodecount_unretained(p->data.expect.x, 0); }
 
   if (p->type == MPC_TYPE_APPLY)    { return 1 + mpc_nodecount_unretained(p->data.apply.x, 0); }
   if (p->type == MPC_TYPE_APPLY_TO) { return 1 + mpc_nodecount_unretained(p->data.apply_to.x, 0); }
   if (p->type == MPC_TYPE_PREDICT)  { return 1 + mpc_nodecount_unretained(p->data.predict.x, 0); }
 
   if (p->type == MPC_TYPE_CHECK)    { return 1 + mpc_nodecount_unretained(p->data.check.x, 0); }
   if (p->type == MPC_TYPE_CHECK_WITH) { return 1 + mpc_nodecount_unretained(p->data.check_with.x, 0); }
 
   if (p->type == MPC_TYPE_NOT)   { return 1 + mpc_nodecount_unretained(p->data.not.x, 0); }
   if (p->type == MPC_TYPE_MAYBE) { return 1 + mpc_nodecount_unretained(p->data.not.x, 0); }
 
   if (p->type == MPC_TYPE_MANY)  { return 1 + mpc_nodecount_unretained(p->data.repeat.x, 0); }
   if (p->type == MPC_TYPE_MANY1) { return 1 + mpc_nodecount_unretained(p->data.repeat.x, 0); }
   if (p->type == MPC_TYPE_COUNT) { return 1 + mpc_nodecount_unretained(p->data.repeat.x, 0); }
 
   if (p->type == MPC_TYPE_OR) {
     total = 1;
     for(i = 0; i < p->data.or.n; i++) {
       total += mpc_nodecount_unretained(p->data.or.xs[i], 0);
     }
     return total;
   }
 
   if (p->type == MPC_TYPE_AND) {
     total = 1;
     for(i = 0; i < p->data.and.n; i++) {
       total += mpc_nodecount_unretained(p->data.and.xs[i], 0);
     }
     return total;
   }
 
   return 1;
 
 }
 
 void mpc_stats(mpc_parser_t* p) {
   printf("Stats\n");
   printf("=====\n");
   printf("Node Count: %i\n", mpc_nodecount_unretained(p, 1));
 }
 
 static void mpc_optimise_unretained(mpc_parser_t *p, int force) {
 
   int i, n, m;
   mpc_parser_t *t;
 
   if (p->retained && !force) { return; }
 
   /* Optimise Subexpressions */
 
   if (p->type == MPC_TYPE_EXPECT)     { mpc_optimise_unretained(p->data.expect.x, 0); }
   if (p->type == MPC_TYPE_APPLY)      { mpc_optimise_unretained(p->data.apply.x, 0); }
   if (p->type == MPC_TYPE_APPLY_TO)   { mpc_optimise_unretained(p->data.apply_to.x, 0); }
   if (p->type == MPC_TYPE_CHECK)      { mpc_optimise_unretained(p->data.check.x, 0); }
   if (p->type == MPC_TYPE_CHECK_WITH) { mpc_optimise_unretained(p->data.check_with.x, 0); }
   if (p->type == MPC_TYPE_PREDICT)    { mpc_optimise_unretained(p->data.predict.x, 0); }
   if (p->type == MPC_TYPE_NOT)        { mpc_optimise_unretained(p->data.not.x, 0); }
   if (p->type == MPC_TYPE_MAYBE)      { mpc_optimise_unretained(p->data.not.x, 0); }
   if (p->type == MPC_TYPE_MANY)       { mpc_optimise_unretained(p->data.repeat.x, 0); }
   if (p->type == MPC_TYPE_MANY1)      { mpc_optimise_unretained(p->data.repeat.x, 0); }
   if (p->type == MPC_TYPE_COUNT)      { mpc_optimise_unretained(p->data.repeat.x, 0); }
 
   if (p->type == MPC_TYPE_OR) {
     for(i = 0; i < p->data.or.n; i++) {
       mpc_optimise_unretained(p->data.or.xs[i], 0);
     }
   }
 
   if (p->type == MPC_TYPE_AND) {
     for(i = 0; i < p->data.and.n; i++) {
       mpc_optimise_unretained(p->data.and.xs[i], 0);
     }
   }
 
   /* Perform optimisations */
 
   while (1) {
 
     /* Merge rhs `or` */
     if (p->type == MPC_TYPE_OR
     &&  p->data.or.xs[p->data.or.n-1]->type == MPC_TYPE_OR
     && !p->data.or.xs[p->data.or.n-1]->retained) {
       t = p->data.or.xs[p->data.or.n-1];
       n = p->data.or.n; m = t->data.or.n;
       p->data.or.n = n + m - 1;
       p->data.or.xs = realloc(p->data.or.xs, sizeof(mpc_parser_t*) * (n + m -1));
       memmove(p->data.or.xs + n - 1, t->data.or.xs, m * sizeof(mpc_parser_t*));
       free(t->data.or.xs); free(t->name); free(t);
       continue;
     }
 
     /* Merge lhs `or` */
     if (p->type == MPC_TYPE_OR
     &&  p->data.or.xs[0]->type == MPC_TYPE_OR
     && !p->data.or.xs[0]->retained) {
       t = p->data.or.xs[0];
       n = p->data.or.n; m = t->data.or.n;
       p->data.or.n = n + m - 1;
       p->data.or.xs = realloc(p->data.or.xs, sizeof(mpc_parser_t*) * (n + m -1));
       memmove(p->data.or.xs + m, p->data.or.xs + 1, (n - 1) * sizeof(mpc_parser_t*));
       memmove(p->data.or.xs, t->data.or.xs, m * sizeof(mpc_parser_t*));
       free(t->data.or.xs); free(t->name); free(t);
       continue;
     }
 
     /* Remove ast `pass` */
     if (p->type == MPC_TYPE_AND
     &&  p->data.and.n == 2
     &&  p->data.and.xs[0]->type == MPC_TYPE_PASS
     && !p->data.and.xs[0]->retained
     &&  p->data.and.f == mpcf_fold_ast) {
       t = p->data.and.xs[1];
       mpc_delete(p->data.and.xs[0]);
       free(p->data.and.xs); free(p->data.and.dxs); free(p->name);
       memcpy(p, t, sizeof(mpc_parser_t));
       free(t);
       continue;
     }
 
     /* Merge ast lhs `and` */
     if (p->type == MPC_TYPE_AND
     &&  p->data.and.f == mpcf_fold_ast
     &&  p->data.and.xs[0]->type == MPC_TYPE_AND
     && !p->data.and.xs[0]->retained
     &&  p->data.and.xs[0]->data.and.f == mpcf_fold_ast) {
       t = p->data.and.xs[0];
       n = p->data.and.n; m = t->data.and.n;
       p->data.and.n = n + m - 1;
       p->data.and.xs = realloc(p->data.and.xs, sizeof(mpc_parser_t*) * (n + m - 1));
       p->data.and.dxs = realloc(p->data.and.dxs, sizeof(mpc_dtor_t) * (n + m - 1 - 1));
       memmove(p->data.and.xs + m, p->data.and.xs + 1, (n - 1) * sizeof(mpc_parser_t*));
       memmove(p->data.and.xs, t->data.and.xs, m * sizeof(mpc_parser_t*));
       for (i = 0; i < p->data.and.n-1; i++) { p->data.and.dxs[i] = (mpc_dtor_t)mpc_ast_delete; }
       free(t->data.and.xs); free(t->data.and.dxs); free(t->name); free(t);
       continue;
     }
 
     /* Merge ast rhs `and` */
     if (p->type == MPC_TYPE_AND
     &&  p->data.and.f == mpcf_fold_ast
     &&  p->data.and.xs[p->data.and.n-1]->type == MPC_TYPE_AND
     && !p->data.and.xs[p->data.and.n-1]->retained
     &&  p->data.and.xs[p->data.and.n-1]->data.and.f == mpcf_fold_ast) {
       t = p->data.and.xs[p->data.and.n-1];
       n = p->data.and.n; m = t->data.and.n;
       p->data.and.n = n + m - 1;
       p->data.and.xs = realloc(p->data.and.xs, sizeof(mpc_parser_t*) * (n + m -1));
       p->data.and.dxs = realloc(p->data.and.dxs, sizeof(mpc_dtor_t) * (n + m - 1 - 1));
       memmove(p->data.and.xs + n - 1, t->data.and.xs, m * sizeof(mpc_parser_t*));
       for (i = 0; i < p->data.and.n-1; i++) { p->data.and.dxs[i] = (mpc_dtor_t)mpc_ast_delete; }
       free(t->data.and.xs); free(t->data.and.dxs); free(t->name); free(t);
       continue;
     }
 
     /* Remove re `lift` */
     if (p->type == MPC_TYPE_AND
     &&  p->data.and.n == 2
     &&  p->data.and.xs[0]->type == MPC_TYPE_LIFT
     &&  p->data.and.xs[0]->data.lift.lf == mpcf_ctor_str
     && !p->data.and.xs[0]->retained
     &&  p->data.and.f == mpcf_strfold) {
       t = p->data.and.xs[1];
       mpc_delete(p->data.and.xs[0]);
       free(p->data.and.xs); free(p->data.and.dxs); free(p->name);
       memcpy(p, t, sizeof(mpc_parser_t));
       free(t);
       continue;
     }
 
     /* Merge re lhs `and` */
     if (p->type == MPC_TYPE_AND
     &&  p->data.and.f == mpcf_strfold
     &&  p->data.and.xs[0]->type == MPC_TYPE_AND
     && !p->data.and.xs[0]->retained
     &&  p->data.and.xs[0]->data.and.f == mpcf_strfold) {
       t = p->data.and.xs[0];
       n = p->data.and.n; m = t->data.and.n;
       p->data.and.n = n + m - 1;
       p->data.and.xs = realloc(p->data.and.xs, sizeof(mpc_parser_t*) * (n + m - 1));
       p->data.and.dxs = realloc(p->data.and.dxs, sizeof(mpc_dtor_t) * (n + m - 1 - 1));
       memmove(p->data.and.xs + m, p->data.and.xs + 1, (n - 1) * sizeof(mpc_parser_t*));
       memmove(p->data.and.xs, t->data.and.xs, m * sizeof(mpc_parser_t*));
       for (i = 0; i < p->data.and.n-1; i++) { p->data.and.dxs[i] = free; }
       free(t->data.and.xs); free(t->data.and.dxs); free(t->name); free(t);
       continue;
     }
 
     /* Merge re rhs `and` */
     if (p->type == MPC_TYPE_AND
     &&  p->data.and.f == mpcf_strfold
     &&  p->data.and.xs[p->data.and.n-1]->type == MPC_TYPE_AND
     && !p->data.and.xs[p->data.and.n-1]->retained
     &&  p->data.and.xs[p->data.and.n-1]->data.and.f == mpcf_strfold) {
       t = p->data.and.xs[p->data.and.n-1];
       n = p->data.and.n; m = t->data.and.n;
       p->data.and.n = n + m - 1;
       p->data.and.xs = realloc(p->data.and.xs, sizeof(mpc_parser_t*) * (n + m -1));
       p->data.and.dxs = realloc(p->data.and.dxs, sizeof(mpc_dtor_t) * (n + m - 1 - 1));
       memmove(p->data.and.xs + n - 1, t->data.and.xs, m * sizeof(mpc_parser_t*));
       for (i = 0; i < p->data.and.n-1; i++) { p->data.and.dxs[i] = free; }
       free(t->data.and.xs); free(t->data.and.dxs); free(t->name); free(t);
       continue;
     }
 
     return;
 
   }
 
 }
 
 void mpc_optimise(mpc_parser_t *p) {
   mpc_optimise_unretained(p, 1);
 }