npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

@stdlib/utils-constructor-name

v0.2.2

Published

Determine the name of a value's constructor.

Downloads

1,618,284

Readme

Constructor Name

NPM version Build Status Coverage Status

Determine the name of a value's constructor.

Installation

npm install @stdlib/utils-constructor-name

Usage

var constructorName = require( '@stdlib/utils-constructor-name' );

constructorName( value )

Returns the name of a value's constructor.

var v = constructorName( 'a' );
// returns 'String'

v = constructorName( 5 );
// returns 'Number'

function Beep() {
    return this;
}
v = constructorName( new Beep() );
// returns 'Beep'

| description | value | constructor | notes | | --------------------- | ----------------------------------- | --------------------- | ------------ | | string | 'beep' | 'String' | | | number | 5 | 'Number' | | | NaN | NaN | 'Number' | | | infinity | +infinity/-infinity | 'Number' | | | boolean | true/false | 'Boolean' | | | null | null | 'Null' | | | undefined | undefined | 'Undefined' | | | array | ['beep', 5] | 'Array' | | | object | {'foo': 'bar'} | 'Object' | | | function | function (){} | 'Function' | | | symbol | Symbol() | 'Symbol' | ES2015 | | regexp | /./ | 'RegExp' | Android 4.1+ | | String | new String('beep') | 'String' | | | Number | new Number(5) | 'Number' | | | Boolean | new Boolean(false) | 'Boolean' | | | Object | new Object() | 'Object' | | | Array | new Array() | 'Array' | | | Int8Array | new Int8Array() | 'Int8Array' | | | Uint8Array | new Uint8Array() | 'Uint8Array' | | | Uint8ClampedArray | new Uint8ClampedArray() | 'Uint8ClampedArray' | | | Int16Array | new Int16Array() | 'Int16Array' | | | Uint16Array | new Uint16Array() | 'Uint16Array' | | | Int32Array | new Int32Array() | 'Int32Array' | | | Uint32Array | new Uint32Array() | 'Uint32Array' | | | Float32Array | new Float32Array() | 'Float32Array' | | | Float64Array | new Float64Array() | 'Float64Array' | | | ArrayBuffer | new ArrayBuffer() | 'ArrayBuffer' | | | Buffer | new Buffer() | 'Buffer' | Node.js | | Date | new Date() | 'Date' | | | RegExp | new RegExp('.') | 'RegExp' | Android 4.1+ | | Function | new Function('x', 'return x') | 'Function' | | | Map | new Map() | 'Map' | ES2015 | | WeakMap | new WeakMap() | 'WeakMap' | ES2015 | | Set | new Set() | 'Set' | ES2015 | | WeakSet | new WeakSet() | 'WeakSet' | ES2015 | | Error | new Error() | 'Error' | | | TypeError | new TypeError() | 'TypeError' | | | SyntaxError | new SyntaxError() | 'SyntaxError' | | | ReferenceError | new ReferenceError() | 'ReferenceError' | | | URIError | new URIError() | 'URIError' | | | RangeError | new RangeError() | 'RangeError' | | | EvalError | new EvalError() | 'EvalError' | | | Math | Math | 'Math' | | | JSON | JSON | 'JSON' | IE8+ | | arguments | (function(){return arguments;})() | 'Arguments' | IE9+ | | custom constructor | new Beep() | 'Beep' | | | anonymous constructor | new (function(){})() | '' | |

Notes

  • If a value's constructor is an anonymous function, the implementation returns an empty string.

    var Beep = function () {
        return this;
    };
    
    var v = constructorName( new Beep() );
    // returns ''

Examples

var Float32Array = require( '@stdlib/array-float32' );
var Float64Array = require( '@stdlib/array-float64' );
var Int8Array = require( '@stdlib/array-int8' );
var Int16Array = require( '@stdlib/array-int16' );
var Int32Array = require( '@stdlib/array-int32' );
var Uint8Array = require( '@stdlib/array-uint8' );
var Uint8ClampedArray = require( '@stdlib/array-uint8c' );
var Uint16Array = require( '@stdlib/array-uint16' );
var Uint32Array = require( '@stdlib/array-uint32' );
var ArrayBuffer = require( '@stdlib/array-buffer' );
var Buffer = require( '@stdlib/buffer-ctor' );
var Symbol = require( '@stdlib/symbol-ctor' );
var constructorName = require( '@stdlib/utils-constructor-name' );

function noop() {
    // Do nothing...
}

var v = constructorName( 'a' );
// returns 'String'

v = constructorName( 5 );
// returns 'Number'

v = constructorName( NaN );
// returns 'Number'

v = constructorName( null );
// returns 'Null'

v = constructorName( void 0 );
// returns 'Undefined'

v = constructorName( true );
// returns 'Boolean'

v = constructorName( false );
// returns 'Boolean'

v = constructorName( {} );
// returns 'Object'

v = constructorName( [] );
// returns 'Array'

v = constructorName( noop );
// returns 'Function'

v = constructorName( /./ );
// returns 'RegExp'

v = constructorName( new Date() );
// returns 'Date'

v = constructorName( new Map() );
// returns 'Map'

v = constructorName( new WeakMap() );
// returns 'WeakMap'

v = constructorName( new Set() );
// returns 'Set'

v = constructorName( new WeakSet() );
// returns 'WeakSet'

v = constructorName( Symbol( 'beep' ) );
// returns 'Symbol'

v = constructorName( new Error() );
// returns 'Error'

v = constructorName( new TypeError() );
// returns 'TypeError'

v = constructorName( new SyntaxError() );
// returns 'SyntaxError'

v = constructorName( new URIError() );
// returns 'URIError'

v = constructorName( new RangeError() );
// returns 'RangeError'

v = constructorName( new ReferenceError() );
// returns 'ReferenceError'

v = constructorName( new EvalError() );
// returns 'EvalError'

v = constructorName( new Int8Array() );
// returns 'Int8Array'

v = constructorName( new Uint8Array() );
// returns 'Uint8Array'

v = constructorName( new Uint8ClampedArray() );
// returns 'Uint8ClampedArray'

v = constructorName( new Int16Array() );
// returns 'Int16Array'

v = constructorName( new Uint16Array() );
// returns 'Uint16Array'

v = constructorName( new Int32Array() );
// returns 'Int32Array'

v = constructorName( new Uint32Array() );
// returns 'Uint32Array'

v = constructorName( new Float32Array() );
// returns 'Float32Array'

v = constructorName( new Float64Array() );
// returns 'Float64Array'

v = constructorName( new ArrayBuffer() );
// returns 'ArrayBuffer'

v = constructorName( new Buffer( 'beep' ) );
// returns 'Buffer'

v = constructorName( Math );
// returns 'Math'

v = constructorName( JSON );
// returns 'JSON'

function Person1() {
    return this;
}
v = constructorName( new Person1() );
// returns 'Person1'

var Person2 = function () {
    return this;
};
v = constructorName( new Person2() );
// returns ''

See Also


Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

Chat


License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.