_baseToString.js
 1  var Symbol = require('./_Symbol'),
 2      arrayMap = require('./_arrayMap'),
 3      isArray = require('./isArray'),
 4      isSymbol = require('./isSymbol');
 5  
 6  /** Used as references for various `Number` constants. */
 7  var INFINITY = 1 / 0;
 8  
 9  /** Used to convert symbols to primitives and strings. */
10  var symbolProto = Symbol ? Symbol.prototype : undefined,
11      symbolToString = symbolProto ? symbolProto.toString : undefined;
12  
13  /**
14   * The base implementation of `_.toString` which doesn't convert nullish
15   * values to empty strings.
16   *
17   * @private
18   * @param {*} value The value to process.
19   * @returns {string} Returns the string.
20   */
21  function baseToString(value) {
22    // Exit early for strings to avoid a performance hit in some environments.
23    if (typeof value == 'string') {
24      return value;
25    }
26    if (isArray(value)) {
27      // Recursively convert values (susceptible to call stack limits).
28      return arrayMap(value, baseToString) + '';
29    }
30    if (isSymbol(value)) {
31      return symbolToString ? symbolToString.call(value) : '';
32    }
33    var result = (value + '');
34    return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
35  }
36  
37  module.exports = baseToString;