extend _.extend(destination, *sources)
Shallowly copy all of the properties in the source objects over to the destination object, and return the destination object. Any nested objects or arrays will be copied by reference, not duplicated. It's in-order, so the last source will override properties of the same name in previous arguments.
_.extend({name: 'moe'}, {age: 50});
=> {name: 'moe', age: 50}
extendOwn _.extendOwn(destination, *sources) Alias : assign
Like extend, but only copies own properties over to the destination object.
pick _.pick(object, *keys)
Return a copy of the object, filtered to only have values for the allowed keys (or array of valid keys). Alternatively accepts a predicate indicating which keys to pick.
_.pick({name: 'moe', age: 50, userid: 'moe1'}, 'name', 'age');
=> {name: 'moe', age: 50}
_.pick({name: 'moe', age: 50, userid: 'moe1'}, function(value, key, object) {
return _.isNumber(value);
});
=> {age: 50}
omit _.omit(object, *keys)
Return a copy of the object, filtered to omit the disallowed keys (or array of keys). Alternatively accepts a predicate indicating which keys to omit.
_.omit({name: 'moe', age: 50, userid: 'moe1'}, 'userid');
=> {name: 'moe', age: 50}
_.omit({name: 'moe', age: 50, userid: 'moe1'}, function(value, key, object) {
return _.isNumber(value);
});
=> {name: 'moe', userid: 'moe1'}
defaults _.defaults(object, *defaults)
Returns object after filling in its undefined properties with the first value present in the following list of defaults objects.
var iceCream = {flavor: "chocolate"};
_.defaults(iceCream, {flavor: "vanilla", sprinkles: "lots"});
=> {flavor: "chocolate", sprinkles: "lots"}
clone _.clone(object)
Create a shallow-copied clone of the provided plain object. Any nested objects or arrays will be copied by reference, not duplicated.
_.clone({name: 'moe'});
=> {name: 'moe'};
tap _.tap(object, interceptor)
Invokes interceptor with the object, and then returns object. The primary purpose of this method is to "tap into" a method chain, in order to perform operations on intermediate results within the chain.
_.chain([1,2,3,200])
.filter(function(num) { return num % 2 == 0; })
.tap(alert)
.map(function(num) { return num * num })
.value();
=> // [2, 200] (alerted)
=> [4, 40000]
toPath _.toPath(path)
Ensures that path is an array. If path is a string, it is wrapped in a single-element array; if it is an array already, it is returned unmodified.
_.toPath('key');
=> ['key']
_.toPath(['a', 0, 'b']);
=> ['a', 0, 'b'] // (same array)
_.toPath is used internally in has, get, invoke, property, propertyOf and result, as well as in iteratee and all functions that depend on it, in order to normalize deep property paths. You can override _.toPath if you want to customize this behavior, for example to enable Lodash-like string path shorthands. Be advised that altering _.toPath will unavoidably cause some keys to become unreachable; override at your own risk.
// Support dotted path shorthands.
var originalToPath = _.toPath;
_.mixin({
toPath: function(path) {
return _.isString(path) ? path.split('.') : originalToPath(path);
}
});
_.get({a: [{b: 5}]}, 'a.0.b');
=> 5
get _.get(object, path, [default])
Returns the specified property of object. path may be specified as a simple key, or as an array of object keys or array indexes, for deep property fetching. If the property does not exist or is undefined, the optional default is returned.
_.get({a: 10}, 'a');
=> 10
_.get({a: [{b: 2}]}, ['a', 0, 'b']);
=> 2
_.get({a: 10}, 'b', 100);
=> 100
has _.has(object, key)
Does the object contain the given key? Identical to object.hasOwnProperty(key), but uses a safe reference to the hasOwnProperty function, in case it's been overridden accidentally.
_.has({a: 1, b: 2, c: 3}, "b");
=> true
property _.property(path)
Returns a function that will return the specified property of any passed-in object. path may be specified as a simple key, or as an array of object keys or array indexes, for deep property fetching.
var stooge = {name: 'moe'};
'moe' === _.property('name')(stooge);
=> true
var stooges = {moe: {fears: {worst: 'Spiders'}}, curly: {fears: {worst: 'Moe'}}};
var curlysWorstFear = _.property(['curly', 'fears', 'worst']);
curlysWorstFear(stooges);
=> 'Moe'
propertyOf _.propertyOf(object)
Inverse of _.property. Takes an object and returns a function which will return the value of a provided property.
var stooge = {name: 'moe'};
_.propertyOf(stooge)('name');
=> 'moe'
