[](http://travis-ci.org/doug-martin/is-extended)
# is-extended
`is-extended` is a Javascript library that can be used standalone or incorporated into [`extended`](https://github.com/doug-martin/extended)
```javascript
var is = require("is-extended");
```
Or
```javascript
var myextended = require("extended")
.register(require("is-extended"));
```
## Installation
```
npm install is-extended
```
Or [download the source](https://raw.github.com/doug-martin/is-extended/master/index.js) ([minified](https://raw.github.com/doug-martin/is-extended/master/is-extended.min.js))
## Usage
`is-extended` includes the following type coercion methods.
* `isFunction` : Test if something is a function
* `isObject` : Test if something is an object.
* `isEmpty` : Test if something is empty.
* `isHash` : Test if something is a hash.
```javascript
is.isHash({}); //true
is.isHash(new Number(1)); //false
is.isObject({}); //true
is.isObject(new Number(1)); //true
```
* `isNumber` : Test if something is a number.
* `isString` : Test if something is a string.
* `isDate` : Test if something is a `Date`.
* `isArray` : Test if something is an `Object`
* `isBoolean` : Test if something is a boolean value.
* `isUndefined` : Test if something is strictly equal to `undefined`.
* `isDefined` : Test if something is strictly not equal to `undefined`.
* `isUndefinedOrNull` : Test if something is strictly equal to `null` or `undefined`.
* `isNull` : Test if something is strictly equal to `null`.
* `isArguments` : Test if something is an `Object`
* `instanceOf` : Test if something is an `Object`
* `isRegExp` : Test if something is a `RegExp`
* `isTrue` : Test if something is strictly equal to `true`
* `isFalse` : Test if something is strictly equal to `false`
* `isNotNull` : Test if something is strictly not equal to `null`.
**`deepEqual`**
Tests if two object are deep equal.
```javascript
is.deepEqual([1,2,3], [1,2,3]); //true
is([1,2,3]).deepEqual([1,2,3]); //true
is.deepEqual({ a: { b: "c"}}, {a : false}); //false
is({ a: { b: "c"}}).deepEqual({ a: { b: "c"}}); //true
```
**`isEq`**
Test if two objects are `==`
**`isNeq`**
Test if two objects are `!=`
**`isSeq`**
Test if two objects are `===`
**`isSneq`**
Test if two objects are `!==`
**`isIn`**
Test if an object is in a array.
```javascript
is.isIn('a', ['a', 'b', 'c']); //true
is('a').isIn(['a', 'b', 'c']); //true
```
**`isNotIn`**
Test if something is not in an array.
```javascript
is.isIn('d', ['a', 'b', 'c']); //true
is('d').isIn(['a', 'b', 'c']); //true
```
**`isLt`**
Check if a value is `<` a given value.
```javascript
is.isLt(1, 2); //true
is("a").isLt("b"); //true
```
**`isLte`**
Check if a value is `<=` a given value.
```javascript
is.isLte(2, 2); //true
is("a").isLte("b"); //true
```
**`isGt`**
Check if a value is `>` a given value.
```javascript
is.isGt(2, 1); //true
is("b").isGt("a"); //true
```
**`isGte`**
Check if a value is `>=` a given value.
```javascript
is.isGte(2, 2); //true
is("b").isLt("a"); //true
```
**`isLike`**
Check if a value is like a given regexp.
```javascript
is.isLike("a", /a/); //true
is.isLike("a", "a"); //true
is(1).isLike(/\d/); //true
is.isLike(1, "\\d"); //true
```
**`isNotLike`**
Check if a value is not like a given regexp.
```javascript
is.isNotLike("a", /\d/); //true
is("a").isNotLike("b"); //true
```
**`contains`**
Checks if an array contains a given value.
```javascript
is.contains([1,2,3], 2); //true
is([1,2,3]).contains(2); //true
```
**`notContains`**
Checks if an array does not contain a given value.
```javascript
is.notContains([1,2,3], 2); //true
is([1,2,3]).notContains(2); //true
```
## Creating a custom tester.
To create a custom type tester you can use the `tester` method.
```javascript
var tester = is.tester().isArray().isDate().isBoolean().tester();
tester([]); //true
tester(new Array()); //true
tester(new Date()); //true
tester(true); //true
tester(false); //true
tester(new Boolean()); //true
tester("hello"); //false
tester(); //false
tester(new String()); //false
tester({}); //false
tester(new Object()); //false
```
## `switcher`
The `is-exteded` `switcher` method allows you to create a structure that executes certain code when a value passes a test.
```javascript
var mySwitcher = is.switcher()
.isLt(0, function (num) {
return num + " is lt 0";
})
.isLte(5, function (num) {
return num + " is gte 0 lte 5";
})
.isLte(10, function (num) {
return num + " is gt 5 lte 10";
})
.isGt(10, function (num) {
return num + " is gt 10";
})
.def(function (num) {
return num + " is unknown value";
})
.switcher();
for (var i = -1; i < 12; i++) {
console.log(mySwitcher(i));
}
```
Outputs the following
```
-1 is lt 0
0 is gte 0 lte 5
1 is gte 0 lte 5
2 is gte 0 lte 5
3 is gte 0 lte 5
4 is gte 0 lte 5
5 is gte 0 lte 5
6 is gt 5 lte 10
7 is gt 5 lte 10
8 is gt 5 lte 10
9 is gt 5 lte 10
10 is gt 5 lte 10
11 is gt 10
```