simple-squiggle

A restricted subset of Squiggle
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AssignmentNode.js (11496B)


      1 import { isAccessorNode, isIndexNode, isNode, isSymbolNode } from '../../utils/is.js';
      2 import { getSafeProperty, setSafeProperty } from '../../utils/customs.js';
      3 import { factory } from '../../utils/factory.js';
      4 import { accessFactory } from './utils/access.js';
      5 import { assignFactory } from './utils/assign.js';
      6 import { getPrecedence } from '../operators.js';
      7 var name = 'AssignmentNode';
      8 var dependencies = ['subset', '?matrix', // FIXME: should not be needed at all, should be handled by subset
      9 'Node'];
     10 export var createAssignmentNode = /* #__PURE__ */factory(name, dependencies, _ref => {
     11   var {
     12     subset,
     13     matrix,
     14     Node
     15   } = _ref;
     16   var access = accessFactory({
     17     subset
     18   });
     19   var assign = assignFactory({
     20     subset,
     21     matrix
     22   });
     23   /**
     24    * @constructor AssignmentNode
     25    * @extends {Node}
     26    *
     27    * Define a symbol, like `a=3.2`, update a property like `a.b=3.2`, or
     28    * replace a subset of a matrix like `A[2,2]=42`.
     29    *
     30    * Syntax:
     31    *
     32    *     new AssignmentNode(symbol, value)
     33    *     new AssignmentNode(object, index, value)
     34    *
     35    * Usage:
     36    *
     37    *    new AssignmentNode(new SymbolNode('a'), new ConstantNode(2))                       // a=2
     38    *    new AssignmentNode(new SymbolNode('a'), new IndexNode('b'), new ConstantNode(2))   // a.b=2
     39    *    new AssignmentNode(new SymbolNode('a'), new IndexNode(1, 2), new ConstantNode(3))  // a[1,2]=3
     40    *
     41    * @param {SymbolNode | AccessorNode} object  Object on which to assign a value
     42    * @param {IndexNode} [index=null]            Index, property name or matrix
     43    *                                            index. Optional. If not provided
     44    *                                            and `object` is a SymbolNode,
     45    *                                            the property is assigned to the
     46    *                                            global scope.
     47    * @param {Node} value                        The value to be assigned
     48    */
     49 
     50   function AssignmentNode(object, index, value) {
     51     if (!(this instanceof AssignmentNode)) {
     52       throw new SyntaxError('Constructor must be called with the new operator');
     53     }
     54 
     55     this.object = object;
     56     this.index = value ? index : null;
     57     this.value = value || index; // validate input
     58 
     59     if (!isSymbolNode(object) && !isAccessorNode(object)) {
     60       throw new TypeError('SymbolNode or AccessorNode expected as "object"');
     61     }
     62 
     63     if (isSymbolNode(object) && object.name === 'end') {
     64       throw new Error('Cannot assign to symbol "end"');
     65     }
     66 
     67     if (this.index && !isIndexNode(this.index)) {
     68       // index is optional
     69       throw new TypeError('IndexNode expected as "index"');
     70     }
     71 
     72     if (!isNode(this.value)) {
     73       throw new TypeError('Node expected as "value"');
     74     } // readonly property name
     75 
     76 
     77     Object.defineProperty(this, 'name', {
     78       get: function () {
     79         if (this.index) {
     80           return this.index.isObjectProperty() ? this.index.getObjectProperty() : '';
     81         } else {
     82           return this.object.name || '';
     83         }
     84       }.bind(this),
     85       set: function set() {
     86         throw new Error('Cannot assign a new name, name is read-only');
     87       }
     88     });
     89   }
     90 
     91   AssignmentNode.prototype = new Node();
     92   AssignmentNode.prototype.type = 'AssignmentNode';
     93   AssignmentNode.prototype.isAssignmentNode = true;
     94   /**
     95    * Compile a node into a JavaScript function.
     96    * This basically pre-calculates as much as possible and only leaves open
     97    * calculations which depend on a dynamic scope with variables.
     98    * @param {Object} math     Math.js namespace with functions and constants.
     99    * @param {Object} argNames An object with argument names as key and `true`
    100    *                          as value. Used in the SymbolNode to optimize
    101    *                          for arguments from user assigned functions
    102    *                          (see FunctionAssignmentNode) or special symbols
    103    *                          like `end` (see IndexNode).
    104    * @return {function} Returns a function which can be called like:
    105    *                        evalNode(scope: Object, args: Object, context: *)
    106    */
    107 
    108   AssignmentNode.prototype._compile = function (math, argNames) {
    109     var evalObject = this.object._compile(math, argNames);
    110 
    111     var evalIndex = this.index ? this.index._compile(math, argNames) : null;
    112 
    113     var evalValue = this.value._compile(math, argNames);
    114 
    115     var name = this.object.name;
    116 
    117     if (!this.index) {
    118       // apply a variable to the scope, for example `a=2`
    119       if (!isSymbolNode(this.object)) {
    120         throw new TypeError('SymbolNode expected as object');
    121       }
    122 
    123       return function evalAssignmentNode(scope, args, context) {
    124         var value = evalValue(scope, args, context);
    125         scope.set(name, value);
    126         return value;
    127       };
    128     } else if (this.index.isObjectProperty()) {
    129       // apply an object property for example `a.b=2`
    130       var prop = this.index.getObjectProperty();
    131       return function evalAssignmentNode(scope, args, context) {
    132         var object = evalObject(scope, args, context);
    133         var value = evalValue(scope, args, context);
    134         setSafeProperty(object, prop, value);
    135         return value;
    136       };
    137     } else if (isSymbolNode(this.object)) {
    138       // update a matrix subset, for example `a[2]=3`
    139       return function evalAssignmentNode(scope, args, context) {
    140         var childObject = evalObject(scope, args, context);
    141         var value = evalValue(scope, args, context);
    142         var index = evalIndex(scope, args, childObject); // Important:  we pass childObject instead of context
    143 
    144         scope.set(name, assign(childObject, index, value));
    145         return value;
    146       };
    147     } else {
    148       // isAccessorNode(node.object) === true
    149       // update a matrix subset, for example `a.b[2]=3`
    150       // we will not use the compile function of the AccessorNode, but compile it
    151       // ourselves here as we need the parent object of the AccessorNode:
    152       // wee need to apply the updated object to parent object
    153       var evalParentObject = this.object.object._compile(math, argNames);
    154 
    155       if (this.object.index.isObjectProperty()) {
    156         var parentProp = this.object.index.getObjectProperty();
    157         return function evalAssignmentNode(scope, args, context) {
    158           var parent = evalParentObject(scope, args, context);
    159           var childObject = getSafeProperty(parent, parentProp);
    160           var index = evalIndex(scope, args, childObject); // Important: we pass childObject instead of context
    161 
    162           var value = evalValue(scope, args, context);
    163           setSafeProperty(parent, parentProp, assign(childObject, index, value));
    164           return value;
    165         };
    166       } else {
    167         // if some parameters use the 'end' parameter, we need to calculate the size
    168         var evalParentIndex = this.object.index._compile(math, argNames);
    169 
    170         return function evalAssignmentNode(scope, args, context) {
    171           var parent = evalParentObject(scope, args, context);
    172           var parentIndex = evalParentIndex(scope, args, parent); // Important: we pass parent instead of context
    173 
    174           var childObject = access(parent, parentIndex);
    175           var index = evalIndex(scope, args, childObject); // Important:  we pass childObject instead of context
    176 
    177           var value = evalValue(scope, args, context);
    178           assign(parent, parentIndex, assign(childObject, index, value));
    179           return value;
    180         };
    181       }
    182     }
    183   };
    184   /**
    185    * Execute a callback for each of the child nodes of this node
    186    * @param {function(child: Node, path: string, parent: Node)} callback
    187    */
    188 
    189 
    190   AssignmentNode.prototype.forEach = function (callback) {
    191     callback(this.object, 'object', this);
    192 
    193     if (this.index) {
    194       callback(this.index, 'index', this);
    195     }
    196 
    197     callback(this.value, 'value', this);
    198   };
    199   /**
    200    * Create a new AssignmentNode having it's childs be the results of calling
    201    * the provided callback function for each of the childs of the original node.
    202    * @param {function(child: Node, path: string, parent: Node): Node} callback
    203    * @returns {AssignmentNode} Returns a transformed copy of the node
    204    */
    205 
    206 
    207   AssignmentNode.prototype.map = function (callback) {
    208     var object = this._ifNode(callback(this.object, 'object', this));
    209 
    210     var index = this.index ? this._ifNode(callback(this.index, 'index', this)) : null;
    211 
    212     var value = this._ifNode(callback(this.value, 'value', this));
    213 
    214     return new AssignmentNode(object, index, value);
    215   };
    216   /**
    217    * Create a clone of this node, a shallow copy
    218    * @return {AssignmentNode}
    219    */
    220 
    221 
    222   AssignmentNode.prototype.clone = function () {
    223     return new AssignmentNode(this.object, this.index, this.value);
    224   };
    225   /*
    226    * Is parenthesis needed?
    227    * @param {node} node
    228    * @param {string} [parenthesis='keep']
    229    * @private
    230    */
    231 
    232 
    233   function needParenthesis(node, parenthesis) {
    234     if (!parenthesis) {
    235       parenthesis = 'keep';
    236     }
    237 
    238     var precedence = getPrecedence(node, parenthesis);
    239     var exprPrecedence = getPrecedence(node.value, parenthesis);
    240     return parenthesis === 'all' || exprPrecedence !== null && exprPrecedence <= precedence;
    241   }
    242   /**
    243    * Get string representation
    244    * @param {Object} options
    245    * @return {string}
    246    */
    247 
    248 
    249   AssignmentNode.prototype._toString = function (options) {
    250     var object = this.object.toString(options);
    251     var index = this.index ? this.index.toString(options) : '';
    252     var value = this.value.toString(options);
    253 
    254     if (needParenthesis(this, options && options.parenthesis)) {
    255       value = '(' + value + ')';
    256     }
    257 
    258     return object + index + ' = ' + value;
    259   };
    260   /**
    261    * Get a JSON representation of the node
    262    * @returns {Object}
    263    */
    264 
    265 
    266   AssignmentNode.prototype.toJSON = function () {
    267     return {
    268       mathjs: 'AssignmentNode',
    269       object: this.object,
    270       index: this.index,
    271       value: this.value
    272     };
    273   };
    274   /**
    275    * Instantiate an AssignmentNode from its JSON representation
    276    * @param {Object} json  An object structured like
    277    *                       `{"mathjs": "AssignmentNode", object: ..., index: ..., value: ...}`,
    278    *                       where mathjs is optional
    279    * @returns {AssignmentNode}
    280    */
    281 
    282 
    283   AssignmentNode.fromJSON = function (json) {
    284     return new AssignmentNode(json.object, json.index, json.value);
    285   };
    286   /**
    287    * Get HTML representation
    288    * @param {Object} options
    289    * @return {string}
    290    */
    291 
    292 
    293   AssignmentNode.prototype.toHTML = function (options) {
    294     var object = this.object.toHTML(options);
    295     var index = this.index ? this.index.toHTML(options) : '';
    296     var value = this.value.toHTML(options);
    297 
    298     if (needParenthesis(this, options && options.parenthesis)) {
    299       value = '<span class="math-paranthesis math-round-parenthesis">(</span>' + value + '<span class="math-paranthesis math-round-parenthesis">)</span>';
    300     }
    301 
    302     return object + index + '<span class="math-operator math-assignment-operator math-variable-assignment-operator math-binary-operator">=</span>' + value;
    303   };
    304   /**
    305    * Get LaTeX representation
    306    * @param {Object} options
    307    * @return {string}
    308    */
    309 
    310 
    311   AssignmentNode.prototype._toTex = function (options) {
    312     var object = this.object.toTex(options);
    313     var index = this.index ? this.index.toTex(options) : '';
    314     var value = this.value.toTex(options);
    315 
    316     if (needParenthesis(this, options && options.parenthesis)) {
    317       value = "\\left(".concat(value, "\\right)");
    318     }
    319 
    320     return object + index + ':=' + value;
    321   };
    322 
    323   return AssignmentNode;
    324 }, {
    325   isClass: true,
    326   isNode: true
    327 });