lang.md

lang

Module Exports

assign

Copies values of own properties from the source object(s) to the target object.

import { assign } from '@dojo/core/lang';

var target = {
	foo: 'bar'
};

var source = {
	bar: 'foo'
};

assign(target, source);

target.foo === 'bar'; // true
target.bar === 'foo'; // true

create

Creates a new object from the given prototype, and copies all enumerable own properties of one or more source objects to the newly created target object.

import { create } from '@dojo/core/lang';

var oldObj = {
	foo: 'bar',
	obj: {
		bar: 'foo'
	}
};

var newObj = create(oldObj, {
	bar: 'foo'
});

newObj.bar === 'foo'; // true
newObj.foo === 'bar'; // true
newObj.obj.bar === 'foo'; // true

oldObj.foo = 'foo';
oldObj.obj.bar = 'bar';

newObj.foo === 'bar'; // true
newObj.obj.bar === 'bar'; // true

deepAssign

Copies the values of all enumerable own properties of one or more source objects to the target object, recursively copying all nested objects and arrays as well.

import { deepAssign } from '@dojo/core/lang';

var oldObj = {
	foo: 'bar',
	obj: {
		bar: 'foo'
	}
};

var newObj = deepAssign(oldObj, {
	bar: 'foo'
});

newObj.bar === 'foo'; // true
newObj.foo === 'bar'; // true
newObj.obj.bar === 'foo'; // true

oldObj.foo = 'foo';
oldObj.obj.bar = 'bar';

newObj.foo === 'bar'; // true
newObj.obj.bar === 'bar'; // true

mixin

Copies values of own and inherited properties from the source object(s) to the target object.

import { mixin } from '@dojo/core/lang';

const obj = {
	foo: 'bar',
	fooObj: {
		bar: 'foo'
	}
};

const result = mixin({}, obj);

result.foo === 'bar'; // true
result.fooObj.bar === 'foo'; // true

obj.fooObj.bar = 'bar';

result.fooObj.bar === 'bar'; // true

deepMixin

Copies the values of all enumerable (own or inherited) properties of one or more source objects to the target object, recursively copying all nested objects and arrays as well.

import { deepMixin } from '@dojo/core/lang';

const obj = {
	foo: 'bar',
	fooObj: {
		bar: 'foo'
	}
};

const result = deepMixin({}, obj);

result.foo === 'bar'; // true
result.fooObj.bar === 'foo'; // true

obj.fooObj.bar = 'bar';

result.fooObj.bar === 'bar'; // false
result.fooObj.bar === 'foo'; // true

duplicate

Creates a new object using the provided source's prototype as the prototype for the new object, and then deep copies the provided source's values into the new target.

import { duplicate } from '@dojo/core/lang';

var oldObj = {
	foo: 'bar'
};

var newObj = duplicate(oldObj);

oldObj.foo = 'foo';

oldObj.foo === 'foo';
newObj.foo === 'bar';

partial

Returns a function which invokes the given function with the given arguments prepended to its argument list. Like Function.prototype.bind, but does not alter execution context.

import { partial } from '@dojo/core/lang';

var add = function (a, b) {
	return a + b;
}

var addFive = partial(add, 5);

var result = addFive(4);

result === 9;

isIdentical

Determines whether two values are the same (including NaN).

import { isIdentical } from '@dojo/core/lang';

isIdentical(1, 1); // true
isIdentical(NaN, NaN); // true

lateBind

Creates a function that calls the current method on an object with given arguments.

import { lateBind } from '@dojo/core/lang';

var person = {
	speak: function (name) {
		return 'hi, ' + name;
	}
};

var personSpeak = lateBind(person, 'speak', 'name');

personSpeak() === 'hi, name'; // true

person.speak = function (name) {
	return 'bye, ' + name;
};

personSpeak() === 'bye, name';