typedescriptor

typedescriptor

typedescriptor identifies and describes types.

Status

Category	Status
Version
Dependencies
Dev dependencies
Build
License

Installation

$ npm install typedescriptor

Quick Start

First you need to add a reference to typedescriptor to your application:

const { Type } = require('typedescriptor');

If you use TypeScript, use the following code instead:

import { Type } from 'typedescriptor';

Then, to identify a value's type, call the static of function and hand over the value:

const type = Type.of('the native web');

console.log(type);
// => 'string'

The types array, boolean, function, null, number, object, string, symbol and undefined are supported.

Getting detailed type descriptions

To get a detailed type descriptor object, call the static from function and hand over the value:

const typeDescriptor = Type.from('the native web');

console.log(typeDescriptor);
// => {
//      name: 'string',
//
//      isValueType: true,
//      isReferenceType: false,
//
//      isArray: false,
//      isBoolean: false,
//      isFunction: false,
//      isNull: false,
//      isNumber: false,
//      isObject: false,
//      isString: true,
//      isSymbol: false,
//      isUndefined: false
//    }

Using TypeScript type guards

Since using the descriptors above doesn't tell TypeScript anything, there are type guards for every type check:

import Type from 'typedescriptor';

const someValue = getSomeValue() as any;

if (Type.isArray(someValue)) {
  // TypeScript now realizes that `someValue` is of type []
}

if (Type.isValueType(someValue)) {
  // TypeScript now realizes that `someValue` is of type string | number | boolean | null | undefined
}

Running quality assurance

To run quality assurance for this module use roboter:

$ npx roboter