Nondeterministic Palindrome Machine

    has-values

    2.0.1 • Public • Published

    has-values NPM version NPM monthly downloads NPM total downloads Linux Build Status

    Returns true if any values exist, false if empty. Works for booleans, functions, numbers, strings, nulls, objects and arrays.

    Please consider following this project's author, Jon Schlinkert, and consider starring the project to show your ❤️ and support.

    Install

    Install with npm:

    $ npm install --save has-values

    Usage

    const has = require('has-values');

    Create an isEmpty function by returning the inverse of the result from has-values:

    const isEmpty = val => !has(val);

    Supported types

    Arrays

    console.log(has(['a']));      //=> true
    console.log(has([0]));        //=> true
    console.log(has([[[]]]));     //=> false
    console.log(has([[], []]));   //=> false
    console.log(has([]));         //=> false

    Booleans

    console.log(has(true));  //=> true
    console.log(has(false)); //=> true

    Buffers

    console.log(has(new Buffer()));      //=> false
    console.log(has(new Buffer('foo'))); //=> true

    Dates

    Dates are always true.

    console.log(has(new Date())); //=> true

    Errors

    Returns false if err.message is an empty string.

    console.log(has(new Error()));      //=> false
    console.log(has(new Error('foo'))); //=> true

    Functions

    Functions are always true.

    console.log(has(function(foo) {})); //=> true
    console.log(has(function() {}));    //=> true

    Maps

    console.log(has(new Map()));                 //=> false
    console.log(has(new Map([['foo', 'bar']]))); //=> true

    Null

    null is always true, as it's assumed that this is a user-defined value, versus undefined which is not.

    console.log(has(null)); //=> true

    Objects

    console.log(has({})); //=> false
    console.log(has({ a: 'a' }}));        //=> true
    console.log(has({ foo: undefined })); //=> false
    console.log(has({ foo: null }));      //=> true

    Numbers

    console.log(has(1)); //=> true
    console.log(has(0)); //=> true

    Regular expressions

    console.log(has(new RegExp()));      //=> false
    console.log(has(new RegExp('foo'))); //=> true

    Sets

    console.log(has(new Set()));               //=> false
    console.log(has(new Set(['foo', 'bar']))); //=> true

    Strings

    console.log(has('a')); //=> true
    console.log(has(''));  //=> false

    Undefined

    console.log(has());          //=> false
    console.log(has(void 0));    //=> false
    console.log(has(undefined)); //=> false

    Release history

    v2.0.0

    • no longer supports numbers as a string
    • optimizations
    • adds support for regex and buffer

    v1.0.0

    • adds support for Map and Set
    • zero always returns true
    • array now recurses, so that an array of empty arrays will return false
    • null now returns true

    About

    Contributing

    Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

    Running Tests

    Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

    $ npm install && npm test
    Building docs

    (This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

    To generate the readme, run the following command:

    $ npm install -g verbose/verb#dev verb-generate-readme && verb

    Related projects

    You might also be interested in these projects:

    Author

    Jon Schlinkert

    License

    Copyright © 2018, Jon Schlinkert. Released under the MIT License.


    This file was generated by verb-generate-readme, v0.6.0, on January 30, 2018.

    Install

    npm i has-values

    DownloadsWeekly Downloads

    33,510,700

    Version

    2.0.1

    License

    MIT

    Last publish

    Collaborators

    • jonschlinkert