Language Utilities. Easier inheritance, scope handling, type checks.
Clone native types like Object, Array, RegExp, Date and primitives.
This method will not clone values that are referenced within val
. It will
only copy the value reference to the new value. If the value is not a plain
object but is an object, it will return the value unchanged.
var a = { foo: 'bar' };
var b = clone(a);
console.log(a === b); // false
console.log(a.foo === b.foo); // true
var c = [1, 2, 3];
var d = clone(b);
console.log(c === d); // false
console.log(c); // [1, 2, 3]
See: deepClone()
Create Object using prototypal inheritance and setting custom properties.
Mix between Douglas Crockford Prototypal Inheritance and object/mixIn
.
parent
(Object) : Parent Object[props]
(Object) : Object propertiesvar base = {
trace : function(){
console.log(this.name);
}
};
var myObj = createObject(base, {
name : 'Lorem Ipsum'
});
myObject.trace(); // "Lorem Ipsum"
Do Function.prototype.apply()
on a constructor while maintaining prototype
chain.
function Person(name, surname) {
this.name = name;
this.surname = surname;
}
Person.prototype.walk = function(){
console.log(this.name +' is walking');
};
var args = ['John', 'Doe'];
// "similar" effect as calling `new Person("John", "Doe")`
var john = ctorApply(Person, args);
john.walk(); // "John is walking"
Deep clone native types like Object, Array, RegExp, Date and primitives.
The instanceClone
function will be invoked to clone objects that are not
"plain" objects (as defined by isPlainObject
) if it is
provided. If instanceClone
is not specified, it will not attempt to clone
non-plain objects, and will copy the object reference.
var a = {foo:'bar', obj: {a:1, b:2}};
var b = deepClone(a); // {foo:'bar', obj: {a:1, b:2}}
console.log( a === b ); // false
console.log( a.obj === b.obj ); // false
var c = [1, 2, [3, 4]];
var d = deepClone(c); // [1, 2, [3, 4]]
var e = c.concat(); // [1, 2, [3, 4]]
console.log( c[2] === d[2] ); // false
// concat doesn't do a deep clone, arrays are passed by reference
console.log( e[2] === d[2] ); // true
function Custom() { }
function cloneCustom(x) { return new Custom(); }
var f = { test: new Custom() };
var g = deepClone(f, cloneCustom);
g.test === f.test // false, since new Custom instance will be created
See: clone()
Return first value that isn't null
or undefined
.
function doSomethingAwesome(foo, bar) {
// default arguments
foo = defaults(foo, 'lorem');
bar = defaults(bar, 123);
// ...
}
Inherit the prototype methods from one constructor into another.
Similar to node.js util/inherits.
It returns the the childCtor.prototype
for convenience.
function Foo(name){
this.name = name;
}
Foo.prototype = {
getName : function(){
return this.name;
}
};
function Bar(name){
Foo.call(this, name);
}
//should be called before calling constructor
var proto = inheritPrototype(Bar, Foo);
// for convenience we return the new prototype object
console.log(proto === Bar.prototype); // true
var myObj = new Bar('lorem ipsum');
myObj.getName(); // "lorem ipsum"
console.log(myObj instanceof Foo); // true
// you also have access to the "super" constructor
console.log(Bar.super_ === Foo); // true
Check if both values are identical/egal.
// wtfjs
NaN === NaN; // false
-0 === +0; // true
is(NaN, NaN); // true
is(-0, +0); // false
is('a', 'b'); // false
See: isnt()
Check if both values are not identical/egal.
// wtfjs
NaN === NaN; // false
-0 === +0; // true
isnt(NaN, NaN); // false
isnt(-0, +0); // true
isnt('a', 'b'); // true
See: is()
If value is an "Arguments" object.
If value is an Array. Uses native ES5 Array.isArray()
if available.
If value is a Boolean.
If value is a Date.
Checks if Array/Object/String is empty.
isEmpty(''); // true
isEmpty('bar'); // false
isEmpty([]); // true
isEmpty([1, 2]); // false
isEmpty({}); // true
isEmpty({a:1, b:2}); // false
Checks if value is Finite.
IMPORTANT: This is not the same as native isFinite
, which will return
true
for values that can be coerced into finite numbers. See
http://es5.github.com/#x15.1.2.5.
isFinite(123); // true
isFinite(Infinity); // false
// this is different than native behavior
isFinite(''); // false
isFinite(true); // false
isFinite([]); // false
isFinite(null); // false
If value is a Function.
If value is of "kind". (used internally by some of the isSomething checks).
Favor the other methods since strings are commonly mistyped and also because
some "kinds" can only be accurately checked by using other methods (e.g.
Arguments
), some of the other checks are also faster.
isKind([1,2], 'Array'); // true
isKind(3, 'Array'); // false
isKind(3, 'Number'); // true
See: kindOf()
Check if value is an integer.
isInteger(123); // true
isInteger(123.45); // false
isInteger({}); // false
isInteger('foo'); // false
isInteger('123'); // false
Check if value is not a number.
It doesn't coerce value into number before doing the check, giving better
results than native isNaN
. Returns true
for everything besides numeric
values.
IMPORTANT: behavior is very different than the native isNaN
and way more
useful!!! See: http://es5.github.io/#x15.1.2.4
isNaN(123); // false
isNaN(NaN); // true
isNaN({}); // true
isNaN(undefined); // true
isNaN([4,5]); // true
// these are all "false" on native isNaN and main reason why this module exists
isNaN(''); // true
isNaN(null); // true
isNaN(true); // true
isNaN(false); // true
isNaN("123"); // true
isNaN([]); // true
isNaN([5]); // true
If value is null
.
If value is a Number.
If value is an Object.
If the value is an Object created by the Object constructor.
If value is a RegExp.
If value is a String.
If value is undefined
.
Gets kind of value (e.g. "String", "Number", "RegExp", "Null", "Date").
Used internally by isKind()
and most of the other isSomething checks.
kindOf([1,2]); // "Array"
kindOf('foo'); // "String"
kindOf(3); // "Number"
See: isKind()
Convert array-like object into Array or wrap value into Array.
toArray({
"0" : "foo",
"1" : "bar",
"length" : 2
}); // ["foo", "bar"]
function foo(){
return toArray(arguments);
}
foo("lorem", 123); // ["lorem", 123]
toArray("lorem ipsum"); // ["lorem ipsum"]
toArray(window); // [window]
toArray({foo:"bar", lorem:123}); // [{foo:"bar", lorem:123}]
See: object/values()
Convert value into number.
// numeric values are typecasted as Number
toNumber('123'); // 123
toNumber(-567); // -567
// falsy values returns zero
toNumber(''); // 0
toNumber(null); // 0
toNumber(undefined); // 0
toNumber(false); // 0
// non-numeric values returns NaN
toNumber('asd'); // NaN
toNumber({}); // NaN
toNumber([]); // NaN
// Date objects return milliseconds since epoch
toNumber(new Date(1985, 6, 23)); // 490935600000
Convert any value to its string representation.
Will return an empty string for undefined
or null
, otherwise will convert
the value to its string representation.
// null and undefined are converted into empty strings
toString(null); // ""
toString(undefined); // ""
toString(1); // "1"
toString([1,2,3]); // "1,2,3"
toString(false); // "false"
// uses `val.toString()` to convert value
toString({toString:funtion(){ return 'foo'; }}); // "foo"
For more usage examples check specs inside /tests
folder. Unit tests are the
best documentation you can get...