mirror of
https://github.com/whoisclebs/lodash.git
synced 2026-02-06 01:47:48 +00:00
99 lines
3.0 KiB
JavaScript
99 lines
3.0 KiB
JavaScript
/**
|
|
* lodash 3.0.0 (Custom Build) <https://lodash.com/>
|
|
* Build: `lodash modern modularize exports="npm" -o ./`
|
|
* Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
|
|
* Based on Underscore.js 1.7.0 <http://underscorejs.org/LICENSE>
|
|
* Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
|
|
* Available under MIT license <https://lodash.com/license>
|
|
*/
|
|
|
|
/**
|
|
* Used as the maximum length of an array-like value.
|
|
* See the [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.max_safe_integer)
|
|
* for more details.
|
|
*/
|
|
var MAX_SAFE_INTEGER = Math.pow(2, 53) - 1;
|
|
|
|
/**
|
|
* Checks if `value` is a valid array-like index.
|
|
*
|
|
* @private
|
|
* @param {*} value The value to check.
|
|
* @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index.
|
|
* @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
|
|
*/
|
|
function isIndex(value, length) {
|
|
value = +value;
|
|
length = length == null ? MAX_SAFE_INTEGER : length;
|
|
return value > -1 && value % 1 == 0 && value < length;
|
|
}
|
|
|
|
/**
|
|
* Checks if the provided arguments are from an iteratee call.
|
|
*
|
|
* @private
|
|
* @param {*} value The potential iteratee value argument.
|
|
* @param {*} index The potential iteratee index or key argument.
|
|
* @param {*} object The potential iteratee object argument.
|
|
* @returns {boolean} Returns `true` if the arguments are from an iteratee call, else `false`.
|
|
*/
|
|
function isIterateeCall(value, index, object) {
|
|
if (!isObject(object)) {
|
|
return false;
|
|
}
|
|
var type = typeof index;
|
|
if (type == 'number') {
|
|
var length = object.length,
|
|
prereq = isLength(length) && isIndex(index, length);
|
|
} else {
|
|
prereq = type == 'string' && index in value;
|
|
}
|
|
return prereq && object[index] === value;
|
|
}
|
|
|
|
/**
|
|
* Checks if `value` is a valid array-like length.
|
|
*
|
|
* **Note:** This function is based on ES `ToLength`. See the
|
|
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-tolength)
|
|
* for more details.
|
|
*
|
|
* @private
|
|
* @param {*} value The value to check.
|
|
* @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
|
|
*/
|
|
function isLength(value) {
|
|
return typeof value == 'number' && value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
|
|
}
|
|
|
|
/**
|
|
* Checks if `value` is the language type of `Object`.
|
|
* (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
|
|
*
|
|
* **Note:** See the [ES5 spec](https://es5.github.io/#x8) for more details.
|
|
*
|
|
* @static
|
|
* @memberOf _
|
|
* @category Lang
|
|
* @param {*} value The value to check.
|
|
* @returns {boolean} Returns `true` if `value` is an object, else `false`.
|
|
* @example
|
|
*
|
|
* _.isObject({});
|
|
* // => true
|
|
*
|
|
* _.isObject([1, 2, 3]);
|
|
* // => true
|
|
*
|
|
* _.isObject(1);
|
|
* // => false
|
|
*/
|
|
function isObject(value) {
|
|
// Avoid a V8 JIT bug in Chrome 19-20.
|
|
// See https://code.google.com/p/v8/issues/detail?id=2291 for more details.
|
|
var type = typeof value;
|
|
return type == 'function' || (value && type == 'object') || false;
|
|
}
|
|
|
|
module.exports = isIterateeCall;
|