extends-type

runtime javascript type assertion with a familiar syntax for typescript lovers

installation

npm i extends-type

usage

import { extendsType } from 'extends-type'

extendsType(
  {
    type: 'string',
    value: 'Hello World',
  },
  '"Hello World"'
) // true
extendsType(
  {
    type: 'string',
    value: 'Hello World',
  },
  'string'
) // true
extendsType(
  {
    type: 'typeof',
    value: () => {
      console.log('hi')
    },
  },
  '() => void'
) // true
extendsType(
  {
    type: 'JSON',
    value: { id: 1 },
  },
  '{ id: 1 }'
) // true

extendsType(
  {
    type: 'string',
    value: 'Not Hello World',
  },
  '"Hello World"'
) // false
extendsType(
  {
    type: 'typeof',
    value: 1,
  },
  'string'
) // false
extendsType(
  {
    type: 'typeof',
    value: () => {
      console.log('hi')
    },
  },
  '() => number'
) // false
extendsType(
  {
    type: 'JSON',
    value: { id: 1 },
  },
  '{ id: 2 }'
) // false