mathjs/src/type/string.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'

const deepMap = require('./../utils/collection/deepMap')
const number = require('../utils/number')

function factory (type, config, load, typed) {
  /**
   * Create a string or convert any object into a string.
   * Elements of Arrays and Matrices are processed element wise.
   *
   * Syntax:
   *
   *    math.string(value)
   *
   * Examples:
   *
   *    math.string(4.2)               // returns string '4.2'
   *    math.string(math.complex(3, 2) // returns string '3 + 2i'
   *
   *    const u = math.unit(5, 'km')
   *    math.string(u.to('m'))         // returns string '5000 m'
   *
   *    math.string([true, false])     // returns ['true', 'false']
   *
   * See also:
   *
   *    bignumber, boolean, complex, index, matrix, number, unit
   *
   * @param {* | Array | Matrix | null} [value]  A value to convert to a string
   * @return {string | Array | Matrix} The created string
   */
  const string = typed('string', {
    '': function () {
      return ''
    },

    'number': number.format,

    'null': function (x) {
      return 'null'
    },

    'boolean': function (x) {
      return x + ''
    },

    'string': function (x) {
      return x
    },

    'Array | Matrix': function (x) {
      return deepMap(x, string)
    },

    'any': function (x) {
      return String(x)
    }
  })

  string.toTex = {
    0: '\\mathtt{""}',
    1: `\\mathrm{string}\\left(\${args[0]}\\right)`
  }

  return string
}

exports.name = 'string'
exports.factory = factory