jiangchengfeiyi-xiaochengxu/node_modules/mathjs/lib/cjs/expression/node/ConditionalNode.js
2025-01-02 11:13:50 +08:00

232 lines
9.8 KiB
JavaScript

"use strict";
var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.createConditionalNode = void 0;
var _defineProperty2 = _interopRequireDefault(require("@babel/runtime/helpers/defineProperty"));
var _is = require("../../utils/is.js");
var _factory = require("../../utils/factory.js");
var _operators = require("../operators.js");
const name = 'ConditionalNode';
const dependencies = ['Node'];
const createConditionalNode = exports.createConditionalNode = /* #__PURE__ */(0, _factory.factory)(name, dependencies, _ref => {
let {
Node
} = _ref;
/**
* Test whether a condition is met
* @param {*} condition
* @returns {boolean} true if condition is true or non-zero, else false
*/
function testCondition(condition) {
if (typeof condition === 'number' || typeof condition === 'boolean' || typeof condition === 'string') {
return !!condition;
}
if (condition) {
if ((0, _is.isBigNumber)(condition)) {
return !condition.isZero();
}
if ((0, _is.isComplex)(condition)) {
return !!(condition.re || condition.im);
}
if ((0, _is.isUnit)(condition)) {
return !!condition.value;
}
}
if (condition === null || condition === undefined) {
return false;
}
throw new TypeError('Unsupported type of condition "' + (0, _is.typeOf)(condition) + '"');
}
class ConditionalNode extends Node {
/**
* A lazy evaluating conditional operator: 'condition ? trueExpr : falseExpr'
*
* @param {Node} condition Condition, must result in a boolean
* @param {Node} trueExpr Expression evaluated when condition is true
* @param {Node} falseExpr Expression evaluated when condition is true
*
* @constructor ConditionalNode
* @extends {Node}
*/
constructor(condition, trueExpr, falseExpr) {
super();
if (!(0, _is.isNode)(condition)) {
throw new TypeError('Parameter condition must be a Node');
}
if (!(0, _is.isNode)(trueExpr)) {
throw new TypeError('Parameter trueExpr must be a Node');
}
if (!(0, _is.isNode)(falseExpr)) {
throw new TypeError('Parameter falseExpr must be a Node');
}
this.condition = condition;
this.trueExpr = trueExpr;
this.falseExpr = falseExpr;
}
get type() {
return name;
}
get isConditionalNode() {
return true;
}
/**
* Compile a node into a JavaScript function.
* This basically pre-calculates as much as possible and only leaves open
* calculations which depend on a dynamic scope with variables.
* @param {Object} math Math.js namespace with functions and constants.
* @param {Object} argNames An object with argument names as key and `true`
* as value. Used in the SymbolNode to optimize
* for arguments from user assigned functions
* (see FunctionAssignmentNode) or special symbols
* like `end` (see IndexNode).
* @return {function} Returns a function which can be called like:
* evalNode(scope: Object, args: Object, context: *)
*/
_compile(math, argNames) {
const evalCondition = this.condition._compile(math, argNames);
const evalTrueExpr = this.trueExpr._compile(math, argNames);
const evalFalseExpr = this.falseExpr._compile(math, argNames);
return function evalConditionalNode(scope, args, context) {
return testCondition(evalCondition(scope, args, context)) ? evalTrueExpr(scope, args, context) : evalFalseExpr(scope, args, context);
};
}
/**
* Execute a callback for each of the child nodes of this node
* @param {function(child: Node, path: string, parent: Node)} callback
*/
forEach(callback) {
callback(this.condition, 'condition', this);
callback(this.trueExpr, 'trueExpr', this);
callback(this.falseExpr, 'falseExpr', this);
}
/**
* Create a new ConditionalNode whose children are the results of calling
* the provided callback function for each child of the original node.
* @param {function(child: Node, path: string, parent: Node): Node} callback
* @returns {ConditionalNode} Returns a transformed copy of the node
*/
map(callback) {
return new ConditionalNode(this._ifNode(callback(this.condition, 'condition', this)), this._ifNode(callback(this.trueExpr, 'trueExpr', this)), this._ifNode(callback(this.falseExpr, 'falseExpr', this)));
}
/**
* Create a clone of this node, a shallow copy
* @return {ConditionalNode}
*/
clone() {
return new ConditionalNode(this.condition, this.trueExpr, this.falseExpr);
}
/**
* Get string representation
* @param {Object} options
* @return {string} str
*/
_toString(options) {
const parenthesis = options && options.parenthesis ? options.parenthesis : 'keep';
const precedence = (0, _operators.getPrecedence)(this, parenthesis, options && options.implicit);
// Enclose Arguments in parentheses if they are an OperatorNode
// or have lower or equal precedence
// NOTE: enclosing all OperatorNodes in parentheses is a decision
// purely based on aesthetics and readability
let condition = this.condition.toString(options);
const conditionPrecedence = (0, _operators.getPrecedence)(this.condition, parenthesis, options && options.implicit);
if (parenthesis === 'all' || this.condition.type === 'OperatorNode' || conditionPrecedence !== null && conditionPrecedence <= precedence) {
condition = '(' + condition + ')';
}
let trueExpr = this.trueExpr.toString(options);
const truePrecedence = (0, _operators.getPrecedence)(this.trueExpr, parenthesis, options && options.implicit);
if (parenthesis === 'all' || this.trueExpr.type === 'OperatorNode' || truePrecedence !== null && truePrecedence <= precedence) {
trueExpr = '(' + trueExpr + ')';
}
let falseExpr = this.falseExpr.toString(options);
const falsePrecedence = (0, _operators.getPrecedence)(this.falseExpr, parenthesis, options && options.implicit);
if (parenthesis === 'all' || this.falseExpr.type === 'OperatorNode' || falsePrecedence !== null && falsePrecedence <= precedence) {
falseExpr = '(' + falseExpr + ')';
}
return condition + ' ? ' + trueExpr + ' : ' + falseExpr;
}
/**
* Get a JSON representation of the node
* @returns {Object}
*/
toJSON() {
return {
mathjs: name,
condition: this.condition,
trueExpr: this.trueExpr,
falseExpr: this.falseExpr
};
}
/**
* Instantiate an ConditionalNode from its JSON representation
* @param {Object} json
* An object structured like
* ```
* {"mathjs": "ConditionalNode",
* "condition": ...,
* "trueExpr": ...,
* "falseExpr": ...}
* ```
* where mathjs is optional
* @returns {ConditionalNode}
*/
static fromJSON(json) {
return new ConditionalNode(json.condition, json.trueExpr, json.falseExpr);
}
/**
* Get HTML representation
* @param {Object} options
* @return {string} str
*/
_toHTML(options) {
const parenthesis = options && options.parenthesis ? options.parenthesis : 'keep';
const precedence = (0, _operators.getPrecedence)(this, parenthesis, options && options.implicit);
// Enclose Arguments in parentheses if they are an OperatorNode
// or have lower or equal precedence
// NOTE: enclosing all OperatorNodes in parentheses is a decision
// purely based on aesthetics and readability
let condition = this.condition.toHTML(options);
const conditionPrecedence = (0, _operators.getPrecedence)(this.condition, parenthesis, options && options.implicit);
if (parenthesis === 'all' || this.condition.type === 'OperatorNode' || conditionPrecedence !== null && conditionPrecedence <= precedence) {
condition = '<span class="math-parenthesis math-round-parenthesis">(</span>' + condition + '<span class="math-parenthesis math-round-parenthesis">)</span>';
}
let trueExpr = this.trueExpr.toHTML(options);
const truePrecedence = (0, _operators.getPrecedence)(this.trueExpr, parenthesis, options && options.implicit);
if (parenthesis === 'all' || this.trueExpr.type === 'OperatorNode' || truePrecedence !== null && truePrecedence <= precedence) {
trueExpr = '<span class="math-parenthesis math-round-parenthesis">(</span>' + trueExpr + '<span class="math-parenthesis math-round-parenthesis">)</span>';
}
let falseExpr = this.falseExpr.toHTML(options);
const falsePrecedence = (0, _operators.getPrecedence)(this.falseExpr, parenthesis, options && options.implicit);
if (parenthesis === 'all' || this.falseExpr.type === 'OperatorNode' || falsePrecedence !== null && falsePrecedence <= precedence) {
falseExpr = '<span class="math-parenthesis math-round-parenthesis">(</span>' + falseExpr + '<span class="math-parenthesis math-round-parenthesis">)</span>';
}
return condition + '<span class="math-operator math-conditional-operator">?</span>' + trueExpr + '<span class="math-operator math-conditional-operator">:</span>' + falseExpr;
}
/**
* Get LaTeX representation
* @param {Object} options
* @return {string} str
*/
_toTex(options) {
return '\\begin{cases} {' + this.trueExpr.toTex(options) + '}, &\\quad{\\text{if }\\;' + this.condition.toTex(options) + '}\\\\{' + this.falseExpr.toTex(options) + '}, &\\quad{\\text{otherwise}}\\end{cases}';
}
}
(0, _defineProperty2.default)(ConditionalNode, "name", name);
return ConditionalNode;
}, {
isClass: true,
isNode: true
});