v8type

Expose V8 C++ type checking to JS

v8type

Module that uses V8 itself to check the type of a given object.

npm install v8type
  • ARRAY - 'array'
  • BOOLEAN - 'boolean'
  • BOOLEAN_OBJECT - 'boolean_object' (new Boolean(false))
  • DATE - 'date'
  • FUNCTION -'function'`
  • NULL - 'null'
  • NUMBER - 'number'
  • NUMBER_OBJECT - 'number_object' (new Number(1))
  • OBJECT - 'object'
  • PRIMITIVE - 'primitive' (useful with v8type.instance function only)
  • REGEXP - 'regexp'
  • STRING - 'string'
  • STRING_OBJECT - 'string_object' (new String('v8type'))
  • UNDEFINED - 'undefined'
  • of(object) - returns the type of object as a string defined in the corresponding constants above.
  • is(object, type) - returns boolean if object matches the string type type (string defined in the corresponding constants above).
  • instance(object, type) - returns boolean is object is of the type type or inherits from type (type is a string defined in the corresponding constants above).
var v8type = require('v8type');
 
console.log(v8type.of([1,2,3,4]));
// 'array' 
 
console.log(v8type.of(undefined));
// 'undefined' 
 
console.log(v8type.of(5));
// 'number' 
 
console.log(v8type.of(new Number(5)))
// 'number_object' 
 
console.log(v8type.of('v8type'));
// 'string' 
 
console.log(v8type.of(new RegExp('v8type')));
// 'regexp' 
 
console.log(v8type.of({}));
// 'object' 
 
console.log(v8type.of(function(){}));
// 'function' 
 
console.log(v8type.of(new Date()));
// 'date' 
var v8type = require('v8type');
 
v8type.is([1,2,3], v8type.ARRAY);
// true 
 
v8type.is({}, v8type.NULL);
// false 
 
// Is does not check inheritence 
v8type.is([], v8type.OBJECT);
// false 
var v8type = require('v8type');
 
v8type.instance([], v8type.ARRAY);
// true 
 
v8type.instance([], v8type.OBJECT);
// true 
 
v8type.instance(5, v8type.OBJECT);
// false 
 
v8type.instance(5, v8type.PRIMITIVE);
// true 
 
v8type.instance(new Number(5), v8type.NUMBER);
// true 
 
v8type.instance(new Number(5), v8type.OBJECT);
// true 

The MIT License (MIT) Copyright (c) 2012 Brett Langdon brett@blangdon.com

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.