lazyValue.js
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var baseWrapperValue = require('./baseWrapperValue'),
getView = require('./getView'),
isArray = require('../lang/isArray');
/** Used as the size to enable large array optimizations. */
var LARGE_ARRAY_SIZE = 200;
/** Used to indicate the type of lazy iteratees. */
var LAZY_FILTER_FLAG = 1,
LAZY_MAP_FLAG = 2;
/* Native method references for those with the same name as other `lodash` methods. */
var nativeMin = Math.min;
/**
* Extracts the unwrapped value from its lazy wrapper.
*
* @private
* @name value
* @memberOf LazyWrapper
* @returns {*} Returns the unwrapped value.
*/
function lazyValue() {
var array = this.__wrapped__.value(),
dir = this.__dir__,
isArr = isArray(array),
isRight = dir < 0,
arrLength = isArr ? array.length : 0,
view = getView(0, arrLength, this.__views__),
start = view.start,
end = view.end,
length = end - start,
index = isRight ? end : (start - 1),
iteratees = this.__iteratees__,
iterLength = iteratees.length,
resIndex = 0,
takeCount = nativeMin(length, this.__takeCount__);
if (!isArr || arrLength < LARGE_ARRAY_SIZE || (arrLength == length && takeCount == length)) {
return baseWrapperValue(array, this.__actions__);
}
var result = [];
outer:
while (length-- && resIndex < takeCount) {
index += dir;
var iterIndex = -1,
value = array[index];
while (++iterIndex < iterLength) {
var data = iteratees[iterIndex],
iteratee = data.iteratee,
type = data.type,
computed = iteratee(value);
if (type == LAZY_MAP_FLAG) {
value = computed;
} else if (!computed) {
if (type == LAZY_FILTER_FLAG) {
continue outer;
} else {
break outer;
}
}
}
result[resIndex++] = value;
}
return result;
}
module.exports = lazyValue;