import isArrayLike from './_isArrayLike.js';
import keys from './keys.js';
import optimizeCb from './_optimizeCb.js';import isArrayLike from './_isArrayLike.js';
import keys from './keys.js';
import optimizeCb from './_optimizeCb.js';Internal helper to create a reducing function, iterating left or right.
export default function createReduce(dir) {Wrap code that reassigns argument variables in a separate function than
the one that accesses arguments.length to avoid a perf hit. (#1991)
var reducer = function(obj, iteratee, memo, initial) {
var _keys = !isArrayLike(obj) && keys(obj),
length = (_keys || obj).length,
index = dir > 0 ? 0 : length - 1;
if (!initial) {
memo = obj[_keys ? _keys[index] : index];
index += dir;
}
for (; index >= 0 && index < length; index += dir) {
var currentKey = _keys ? _keys[index] : index;
memo = iteratee(memo, obj[currentKey], currentKey, obj);
}
return memo;
};
return function(obj, iteratee, memo, context) {
var initial = arguments.length >= 3;
return reducer(obj, optimizeCb(iteratee, context, 4), memo, initial);
};
}