@phragon-util/proof

Functions for validating an expression or variable. A value is not valid if it is null, undefined, false. If value is a number it must be finite and not NaN. An empty string and a zero number is allowed.

This library is built for the PhragonJS framework and uses the @phragon-util/global-var package. If you are not using PhragonJS, you should add a cleaner for __*__ global variables and functions to your build manager (Webpack, Rollup, etc.)

❯ Install

$ npm install --save @phragon-util/proof

Usage

All functions always return void.
The warning function and the warningOnce function throw an error and catch it, you can use this behavior for debugging (only in production mode).

import { invariant, warning, warningOnce } from "@phragon-util/proof";

// throw Error("some message")
invariant(false, "some message");

// "some message" warning in console
warning(false, "some mesage");

// "some message" warning in console
// just one repeat for "my-key"
warningOnce("my-key", false, "some message");