type-name

Just a reasonable typeof

DESCRIPTION

typeName function returns reasonable type name for input value.

| description | input | result | |:---------------|:--------|:------------| | null literal | null | 'null' | | undefined value | undefined | 'undefined' | | string literal | 'foo' | 'string' | | number literal | 5 | 'number' | | boolean literal | false | 'boolean' | | regexp literal (Android 4.1+) | /^not/ | 'RegExp' | | array literal | ['foo', 4] | 'Array' | | object literal | {name: 'bar'} | 'Object' (be careful!) | | function expression | function () {} | 'function' | | String object | new String('foo') | 'String' | | Number object | new Number('3') | 'Number' | | Boolean object |new Boolean('1') | 'Boolean' | | Date object | new Date() | 'Date' | | RegExp object (Android 4.1+) | new RegExp('^not', 'g') | 'RegExp' | | Array object | new Array() | 'Array' | | Object object | new Object() | 'Object' | | Function object | new Function('x', 'y', 'return x + y') | 'function' (be careful!) | | Error object | new Error('error!') | 'Error' | | TypeError object | new TypeError('type error!') | 'TypeError' | | NaN | NaN | 'number' | | Infinity | Infinity | 'number' | | Math | Math | 'Math' | | JSON (IE8+) | JSON | 'JSON' | | arguments object (IE9+) | (function(){ return arguments; })() | 'Arguments' | | User-defined constructor | new Person('alice', 5) | 'Person' | | Anonymous constructor | new AnonPerson('bob', 4) | '' | | Named class | new(class Foo { constructor() {} }) | 'Foo' | | Anonymous class | new(class { constructor() {} }) | '' | | Symbol | Symbol("FOO") | 'symbol' | | Promise | Promise.resolve(1) | 'Promise' |

EXAMPLE

var typeName = require('type-name');
var assert = require('assert');

assert(typeName(null) === 'null');
assert(typeName(undefined) === 'undefined');
assert(typeName('foo') === 'string');
assert(typeName(5) === 'number');
assert(typeName(false) === 'boolean');
assert(typeName(/^not/) === 'RegExp');
assert(typeName(['foo', 4]) === 'Array');
assert(typeName({name: 'bar'}) === 'Object');
assert(typeName(function () {}) === 'function');
assert(typeName(new String('foo')) === 'String');
assert(typeName(new Number('3')) === 'Number');
assert(typeName(new Boolean('1')) === 'Boolean');
assert(typeName(new Date()) === 'Date');
assert(typeName(new RegExp('^not', 'g')) === 'RegExp');
assert(typeName(new Array()) === 'Array');
assert(typeName(new Object()) === 'Object');
assert(typeName(new Function('x', 'y', 'return x + y')) === 'function');
assert(typeName(new Error('error!')) === 'Error');
assert(typeName(new TypeError('type error!')) === 'TypeError');
assert(typeName(NaN) === 'number');
assert(typeName(Infinity) === 'number');
assert(typeName(Math) === 'Math');
assert(typeName(JSON) === 'JSON'); // IE8+
assert(typeName((function(){ return arguments; })()) === 'Arguments');  // IE9+
assert(typeName(Symbol("FOO")) === 'symbol');
assert(typeName(Promise.resolve(1)) === 'Promise');

function Person(name, age) {
    this.name = name;
    this.age = age;
}

var AnonPerson = function(name, age) {
    this.name = name;
    this.age = age;
};

assert(typeName(new Person('alice', 5)) === 'Person');
assert(typeName(new AnonPerson('bob', 4)) === '');

assert(typeName(new(class Foo { constructor() {} })) === 'Foo');
assert(typeName(new(class { constructor() {} })) === '');

INSTALL

via npm

Install

$ npm install --save type-name

Use

var typeName = require('type-name');
console.log(typeName(anyVar));

use type-name npm module on browser

typeName function is exported

<script type="text/javascript" src="./path/to/node_modules/type-name/build/type-name.js"></script>

via bower

Install

$ bower install --save type-name

Load (typeName function is exported)

<script type="text/javascript" src="./path/to/bower_components/type-name/build/type-name.js"></script>

Use

console.log(typeName(anyVar));

AUTHOR

• Takuto Wada

CONTRIBUTORS

• azu
• Yosuke Furukawa
• Athan
• Andrew Moss

LICENSE

Licensed under the MIT license.