mathjs/src/type/chain/function/chain.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 factory (type, config, load, typed) {
  /**
   * Wrap any value in a chain, allowing to perform chained operations on
   * the value.
   *
   * All methods available in the math.js library can be called upon the chain,
   * and then will be evaluated with the value itself as first argument.
   * The chain can be closed by executing `chain.done()`, which returns
   * the final value.
   *
   * The chain has a number of special functions:
   *
   * - `done()`     Finalize the chain and return the chain's value.
   * - `valueOf()`  The same as `done()`
   * - `toString()` Executes `math.format()` onto the chain's value, returning
   *                a string representation of the value.
   *
   * Syntax:
   *
   *    math.chain(value)
   *
   * Examples:
   *
   *     math.chain(3)
   *         .add(4)
   *         .subtract(2)
   *         .done()     // 5
   *
   *     math.chain( [[1, 2], [3, 4]] )
   *         .subset(math.index(0, 0), 8)
   *         .multiply(3)
   *         .done()     // [[24, 6], [9, 12]]
   *
   * @param {*} [value]   A value of any type on which to start a chained operation.
   * @return {math.type.Chain} The created chain
   */
  return typed('chain', {
    '': function () {
      return new type.Chain()
    },

    'any': function (value) {
      return new type.Chain(value)
    }
  })
}

exports.name = 'chain'
exports.factory = factory