mathjs/lib/utils/function.js

Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser with support for symbolic computation, comes with a large set of built-in functions and constants, and offers an integrated solution to work with dif

'use strict'; // function utils

/**
 * Memoize a given function by caching the computed result.
 * The cache of a memoized function can be cleared by deleting the `cache`
 * property of the function.
 *
 * @param {function} fn                     The function to be memoized.
 *                                          Must be a pure function.
 * @param {function(args: Array)} [hasher]  A custom hash builder.
 *                                          Is JSON.stringify by default.
 * @return {function}                       Returns the memoized function
 */

function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }

exports.memoize = function (fn, hasher) {
  return function memoize() {
    if (_typeof(memoize.cache) !== 'object') {
      memoize.cache = {};
    }

    var args = [];

    for (var i = 0; i < arguments.length; i++) {
      args[i] = arguments[i];
    }

    var hash = hasher ? hasher(args) : JSON.stringify(args);

    if (!(hash in memoize.cache)) {
      memoize.cache[hash] = fn.apply(fn, args);
    }

    return memoize.cache[hash];
  };
};
/**
 * Find the maximum number of arguments expected by a typed function.
 * @param {function} fn   A typed function
 * @return {number} Returns the maximum number of expected arguments.
 *                  Returns -1 when no signatures where found on the function.
 */


exports.maxArgumentCount = function (fn) {
  return Object.keys(fn.signatures || {}).reduce(function (args, signature) {
    var count = (signature.match(/,/g) || []).length + 1;
    return Math.max(args, count);
  }, -1);
};
/**
 * Call a typed function with the
 * @param {function} fn   A function or typed function
 * @return {number} Returns the maximum number of expected arguments.
 *                  Returns -1 when no signatures where found on the function.
 */


exports.callWithRightArgumentCount = function (fn, args, argCount) {
  return Object.keys(fn.signatures || {}).reduce(function (args, signature) {
    var count = (signature.match(/,/g) || []).length + 1;
    return Math.max(args, count);
  }, -1);
};