Determine the name of a value's constructor.
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var constructorName = require( '@stdlib/utils-constructor-name' );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(){})() |
'' |
-
If a value's constructor is an anonymous
function, the implementation returns an emptystring.var Beep = function () { return this; }; var v = constructorName( new Beep() ); // returns ''
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 ''@stdlib/utils-function-name: determine a function's name.
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