You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
65 lines
2.2 KiB
65 lines
2.2 KiB
import arrayEach from './_arrayEach.js'; |
|
import baseCreate from './_baseCreate.js'; |
|
import baseForOwn from './_baseForOwn.js'; |
|
import baseIteratee from './_baseIteratee.js'; |
|
import getPrototype from './_getPrototype.js'; |
|
import isArray from './isArray.js'; |
|
import isBuffer from './isBuffer.js'; |
|
import isFunction from './isFunction.js'; |
|
import isObject from './isObject.js'; |
|
import isTypedArray from './isTypedArray.js'; |
|
|
|
/** |
|
* An alternative to `_.reduce`; this method transforms `object` to a new |
|
* `accumulator` object which is the result of running each of its own |
|
* enumerable string keyed properties thru `iteratee`, with each invocation |
|
* potentially mutating the `accumulator` object. If `accumulator` is not |
|
* provided, a new object with the same `[[Prototype]]` will be used. The |
|
* iteratee is invoked with four arguments: (accumulator, value, key, object). |
|
* Iteratee functions may exit iteration early by explicitly returning `false`. |
|
* |
|
* @static |
|
* @memberOf _ |
|
* @since 1.3.0 |
|
* @category Object |
|
* @param {Object} object The object to iterate over. |
|
* @param {Function} [iteratee=_.identity] The function invoked per iteration. |
|
* @param {*} [accumulator] The custom accumulator value. |
|
* @returns {*} Returns the accumulated value. |
|
* @example |
|
* |
|
* _.transform([2, 3, 4], function(result, n) { |
|
* result.push(n *= n); |
|
* return n % 2 == 0; |
|
* }, []); |
|
* // => [4, 9] |
|
* |
|
* _.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) { |
|
* (result[value] || (result[value] = [])).push(key); |
|
* }, {}); |
|
* // => { '1': ['a', 'c'], '2': ['b'] } |
|
*/ |
|
function transform(object, iteratee, accumulator) { |
|
var isArr = isArray(object), |
|
isArrLike = isArr || isBuffer(object) || isTypedArray(object); |
|
|
|
iteratee = baseIteratee(iteratee, 4); |
|
if (accumulator == null) { |
|
var Ctor = object && object.constructor; |
|
if (isArrLike) { |
|
accumulator = isArr ? new Ctor : []; |
|
} |
|
else if (isObject(object)) { |
|
accumulator = isFunction(Ctor) ? baseCreate(getPrototype(object)) : {}; |
|
} |
|
else { |
|
accumulator = {}; |
|
} |
|
} |
|
(isArrLike ? arrayEach : baseForOwn)(object, function(value, index, object) { |
|
return iteratee(accumulator, value, index, object); |
|
}); |
|
return accumulator; |
|
} |
|
|
|
export default transform;
|
|
|