Function toKey

lodash.js:6848–6854

* Converts `value` to a string key if it's not a string or symbol. * * @private * @param {*} value The value to inspect. * @returns {string|symbol} Returns the key.

(value)

     * @returns {string|symbol} Returns the key.
     */
    function toKey(value) {
      if (typeof value == 'string' || isSymbol(value)) {
        return value;
      }
      var result = (value + '');
      return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
    }

    /**
     * Converts `func` to its source code.