_(value)
Creates a lodash object, which wraps the given value, to enable method chaining.
In addition to Lo-Dash methods, wrappers also have the following Array methods:
concat, join, pop, push, reverse, shift, slice, sort, splice, and unshift
Chaining is supported in custom builds as long as the value method is implicitly or explicitly included in the build.
The chainable wrapper functions are:
after, assign, bind, bindAll, bindKey, chain, compact, compose, concat, countBy, createCallback, debounce, defaults, defer, delay, difference, filter, flatten, forEach, forIn, forOwn, functions, groupBy, initial, intersection, invert, invoke, keys, map, max, memoize, merge, min, object, omit, once, pairs, partial, partialRight, pick, pluck, push, range, reject, rest, reverse, shuffle, slice, sort, sortBy, splice, tap, throttle, times, toArray, transform, union, uniq, unshift, unzip, values, where, without, wrap, and zip
The non-chainable wrapper functions are:
clone, cloneDeep, contains, escape, every, find, has, identity, indexOf, isArguments, isArray, isBoolean, isDate, isElement, isEmpty, isEqual, isFinite, isFunction, isNaN, isNull, isNumber, isObject, isPlainObject, isRegExp, isString, isUndefined, join, lastIndexOf, mixin, noConflict, parseInt, pop, random, reduce, reduceRight, result, shift, size, some, sortedIndex, runInContext, template, unescape, uniqueId, and value
The wrapper functions first and last return wrapped values when n is passed, otherwise they return unwrapped values.
Aliases
chain
Arguments
- value(Mixed): The value to wrap in a- lodashinstance.
Returns
(Object): Returns a lodash instance.
Example
var wrapped = _([1, 2, 3]);
// returns an unwrapped value
wrapped.reduce(function(sum, num) {
return sum + num;
});
// => 6
// returns a wrapped value
var squares = wrapped.map(function(num) {
return num * num;
});
_.isArray(squares);
// => false
_.isArray(squares.value());
// => true
_.tap(value, interceptor)
Invokes interceptor with the value as the first argument, and then returns value. The purpose of this method is to “tap into” a method chain, in order to perform operations on intermediate results within the chain.
Arguments
- value(Mixed): The value to pass to- interceptor.
- interceptor(Function): The function to invoke.
Returns
(Mixed): Returns value.
Example
_([1, 2, 3, 4])
.filter(function(num) { return num % 2 == 0; })
.tap(alert)
.map(function(num) { return num * num; })
.value();
// => // [2, 4] (alerted)
// => [4, 16]
_.prototype.toString()
Produces the toString result of the wrapped value.
Returns
(String): Returns the string result.
Example
_([1, 2, 3]).toString();
// => '1,2,3'
_.prototype.valueOf()
Extracts the wrapped value.
Aliases
value
Returns
(Mixed): Returns the wrapped value.
Example
_([1, 2, 3]).valueOf();
// => [1, 2, 3]
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