isFunction.js
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var baseIsFunction = require('../internal/baseIsFunction'),
isNative = require('./isNative');
/** `Object#toString` result references. */
var funcTag = '[object Function]';
/** Used for native method references. */
var objectProto = Object.prototype;
/**
* Used to resolve the [`toStringTag`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-object.prototype.tostring)
* of values.
*/
var objToString = objectProto.toString;
/** Native method references. */
var Uint8Array = isNative(Uint8Array = global.Uint8Array) && Uint8Array;
/**
* Checks if `value` is classified as a `Function` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isFunction(_);
* // => true
*
* _.isFunction(/abc/);
* // => false
*/
var isFunction = !(baseIsFunction(/x/) || (Uint8Array && !baseIsFunction(Uint8Array))) ? baseIsFunction : function(value) {
// The use of `Object#toString` avoids issues with the `typeof` operator
// in older versions of Chrome and Safari which return 'function' for regexes
// and Safari 8 equivalents which return 'object' for typed array constructors.
return objToString.call(value) == funcTag;
};
module.exports = isFunction;