node package manager

type-name

Just a reasonable typeof

type-name

Just a reasonable typeof

Build Status NPM version Dependency Status License

Sauce Test Status

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

CONTRIBUTORS

LICENSE

Licensed under the MIT license.