An invariant function, which takes a condition and a optional message value, and throw an error when the given condition fails.

Install

• npm

  npm install --save @yozora/invariant

Usage

• Syntax

  function invariant(
    condition: boolean,
    message?: string | (() => string),
  ): asserts condition

• Demo

  import invariant from '@yozora/invariant'
  
  invariant(typeof window !== 'undefined', '`window` is not defined.')
  invariant(typeof window !== 'undefined', () => '`window` is not defined:' + window)

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