invert.js
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var constant = require('./constant'),
createInverter = require('./_createInverter'),
identity = require('./identity');
/** Used for built-in method references. */
var objectProto = Object.prototype;
/**
* Used to resolve the
* [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
* of values.
*/
var nativeObjectToString = objectProto.toString;
/**
* Creates an object composed of the inverted keys and values of `object`.
* If `object` contains duplicate values, subsequent values overwrite
* property assignments of previous values.
*
* @static
* @memberOf _
* @since 0.7.0
* @category Object
* @param {Object} object The object to invert.
* @returns {Object} Returns the new inverted object.
* @example
*
* var object = { 'a': 1, 'b': 2, 'c': 1 };
*
* _.invert(object);
* // => { '1': 'c', '2': 'b' }
*/
var invert = createInverter(function(result, value, key) {
if (value != null &&
typeof value.toString != 'function') {
value = nativeObjectToString.call(value);
}
result[value] = key;
}, constant(identity));
module.exports = invert;