simple-squiggle

A restricted subset of Squiggle
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index.js (2730B)

      1 "use strict";
      2 
      3 // Map the characters to escape to their escaped values. The list is derived
      4 // from http://www.cespedes.org/blog/85/how-to-escape-latex-special-characters
      5 
      6 var _extends = Object.assign || function (target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i]; for (var key in source) { if (Object.prototype.hasOwnProperty.call(source, key)) { target[key] = source[key]; } } } return target; };
      7 
      8 var defaultEscapes = {
      9   "{": "\\{",
     10   "}": "\\}",
     11   "\\": "\\textbackslash{}",
     12   "#": "\\#",
     13   $: "\\$",
     14   "%": "\\%",
     15   "&": "\\&",
     16   "^": "\\textasciicircum{}",
     17   _: "\\_",
     18   "~": "\\textasciitilde{}"
     19 };
     20 var formatEscapes = {
     21   "\u2013": "\\--",
     22   "\u2014": "\\---",
     23   " ": "~",
     24   "\t": "\\qquad{}",
     25   "\r\n": "\\newline{}",
     26   "\n": "\\newline{}"
     27 };
     28 
     29 var defaultEscapeMapFn = function defaultEscapeMapFn(defaultEscapes, formatEscapes) {
     30   return _extends({}, defaultEscapes, formatEscapes);
     31 };
     32 
     33 /**
     34  * Escape a string to be used in LaTeX documents.
     35  * @param {string} str the string to be escaped.
     36  * @param {boolean} params.preserveFormatting whether formatting escapes should
     37  *  be performed (default: false).
     38  * @param {function} params.escapeMapFn the function to modify the escape maps.
     39  * @return {string} the escaped string, ready to be used in LaTeX.
     40  */
     41 module.exports = function (str) {
     42   var _ref = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {},
     43       _ref$preserveFormatti = _ref.preserveFormatting,
     44       preserveFormatting = _ref$preserveFormatti === undefined ? false : _ref$preserveFormatti,
     45       _ref$escapeMapFn = _ref.escapeMapFn,
     46       escapeMapFn = _ref$escapeMapFn === undefined ? defaultEscapeMapFn : _ref$escapeMapFn;
     47 
     48   var runningStr = String(str);
     49   var result = "";
     50 
     51   var escapes = escapeMapFn(_extends({}, defaultEscapes), preserveFormatting ? _extends({}, formatEscapes) : {});
     52   var escapeKeys = Object.keys(escapes); // as it is reused later on
     53 
     54   // Algorithm: Go through the string character by character, if it matches
     55   // with one of the special characters then we'll replace it with the escaped
     56   // version.
     57 
     58   var _loop = function _loop() {
     59     var specialCharFound = false;
     60     escapeKeys.forEach(function (key, index) {
     61       if (specialCharFound) {
     62         return;
     63       }
     64       if (runningStr.length >= key.length && runningStr.slice(0, key.length) === key) {
     65         result += escapes[escapeKeys[index]];
     66         runningStr = runningStr.slice(key.length, runningStr.length);
     67         specialCharFound = true;
     68       }
     69     });
     70     if (!specialCharFound) {
     71       result += runningStr.slice(0, 1);
     72       runningStr = runningStr.slice(1, runningStr.length);
     73     }
     74   };
     75 
     76   while (runningStr) {
     77     _loop();
     78   }
     79   return result;
     80 };