Last updated 4 months ago

Insist on a method/property/staticProperty/configuration presence

This stamp (aka behavior) will throw if a method (property, staticProperty, configuration, etc) is missing at object creation.


import Required from '@stamp/required'
const InsistOnRedrawMethod = Required.required({methods: {redraw: Required}})

Or if you don't want to import the stamp you can import only the method:

import {required} from '@stamp/required'
const InsistOnRedrawMethod = required({methods: {redraw: required}})


Static methods


Setup which things are required stamp.required({METATYPE: {KEY: required}}) -> Stamp


import stampit from '@stamp/it'
import Required, {required} from '@stamp/required'
const requiredConfigurationDifficulty = required({configuration: {difficulty: required}})
const requiredMethodMove = required({methods: {move: Required}})
const requiredPropertyGuild = Required.required({properties: {guild: required}})
let Paladin = stampit({
props: {
mana: 50,
strength: 50,
health: 100
const paladin = Paladin() // ok
Paladin = Paladin.compose(
const paladin = Paladin() // THROWS - Required: There must be difficulty in this stamp configuration
Paladin = Paladin.conf({ difficulty: 5 })
const paladin = Paladin() // THROWS - Required: There must be move in this stamp methods
Paladin = Paladin.methods({
move(x, y) {
// ... implementation
const paladin = Paladin() // THROWS - Required: There must be guild in this stamp properties
Paladin = Paladin.props({ guild: 'Warriors of Light' })
const paladin = Paladin() // ok