invariant-slim

    1.0.5 • Public • Published

    invariant-slim

    A simpler version of Facebook's invariant implementation from React.

    Installation

    invariant-slim is available as an npm package. Simply run npm install invariant-slim command.

    To use it in your project:

    import invariant from 'invariant-slim'; // ES6 syntax
    var invariant = require('invariant-slim'); // ES5 syntax
    

    Usage

    Use invariant() to assert state which your program assumes to be true.

    Pass in a condition to be evaluated and a format to be displayed as an error message. The format respects the sprintf-style syntax ('%s' will be replaced by whatever arguments are passed in).

    Examples:

    The following code will not throw:

    invariant(
      true,
      'Demo message'
    );
    

    The following code will throw with a static message and will output the following error in the console - 'Invariant Violation: A static error message':

    invariant(
      false,
      'A static error message'
    );
    

    The following code will throw with a dynamic formatted error message and will output the following error in the console - 'Invariant Violation: A dynamic error message arg1,arg2':

    invariant(
      false,
      'A dynamic error message %s',
      ['arg1', 'arg2']
    );
    

    License

    This software is released under the terms of WTFPL v2.0 license.

    Install

    npm i invariant-slim

    DownloadsWeekly Downloads

    2

    Version

    1.0.5

    License

    WTFPL-2.0

    Last publish

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