has-value

    2.0.2 • Public • Published

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

    Returns true if a value exists, false if empty. Works with deeply nested values using object paths.

    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-value

    Heads up!

    Breaking changes in v2.0! See the release history for details.

    Usage

    const has = require('has-value');
     
    console.log(has()) //=> true
    console.log(has('foo')) //=> true

    Works for:

    • booleans
    • functions
    • numbers
    • strings
    • nulls
    • object
    • arrays

    isEmpty

    To do the opposite and test for empty values, do:

    const isEmpty = (...args) => !has(...args);

    Supported types

    Arrays

    console.log(has({ foo: { bar: ['a'] } }, 'foo.bar'));    //=> true
    console.log(has({ foo: { bar: [0] } }, 'foo.bar'));      //=> true
    console.log(has({ foo: { bar: [[[]]] } }, 'foo.bar'));   //=> false
    console.log(has({ foo: { bar: [[], []] } }, 'foo.bar')); //=> false
    console.log(has({ foo: { bar: [] } }, 'foo.bar'));       //=> false

    Booleans

    console.log(has({ foo: { bar: true } }, 'foo.bar'));  //=> true
    console.log(has({ foo: { bar: false } }, 'foo.bar')); //=> true

    Buffers

    console.log(has({ foo: { bar: new Buffer() } }, 'foo.bar'));      //=> false
    console.log(has({ foo: { bar: new Buffer('foo') } }, 'foo.bar')); //=> true

    Dates

    Dates are always true.

    console.log(has({ foo: { bar: new Date() } }, 'foo.bar')); //=> true

    Errors

    Returns false if err.message is an empty string.

    console.log(has({ foo: { bar: new Error() } }, 'foo.bar'));      //=> false
    console.log(has({ foo: { bar: new Error('foo') } }, 'foo.bar')); //=> true

    Functions

    Functions are always true.

    console.log(has({ foo: { bar: function(foo) {} } }, 'foo.bar')); //=> true
    console.log(has({ foo: { bar: function() {} } }, 'foo.bar'));    //=> true

    Maps

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

    Objects

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

    Numbers

    console.log(has({ foo: { bar: 1 } }, 'foo.bar')); //=> true
    console.log(has({ foo: { bar: 0 } }, 'foo.bar')); //=> true

    Regular expressions

    console.log(has({ foo: { bar: new RegExp() } }, 'foo.bar'));      //=> false
    console.log(has({ foo: { bar: new RegExp('foo') } }, 'foo.bar')); //=> true

    Sets

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

    Strings

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

    Undefined

    console.log(has({ foo: { bar:  } }, 'foo.bar'));          //=> false
    console.log(has({ foo: { bar: void 0 } }, 'foo.bar'));    //=> false
    console.log(has({ foo: { bar: undefined } }, 'foo.bar')); //=> false

    Release history

    v2.0.0

    Breaking changes

    • Now returns false if the first argument is not an object, function or array, and the second argument is not a string or array.

    v1.0.0

    • 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:

    • define-property: Define a non-enumerable property on an object. Uses Reflect.defineProperty when available, otherwise Object.defineProperty. | homepage
    • get-value: Use property paths like 'a.b.c' to get a nested value from an object. Even works… more | homepage
    • set-value: Create nested values and any intermediaries using dot notation ('a.b.c') paths. | homepage
    • unset-value: Delete nested properties from an object using dot notation. | homepage

    Contributors

    Commits Contributor
    32 jonschlinkert
    2 rmharrison
    1 wtgtybhertgeghgtwtg

    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 March 03, 2018.

    Install

    npm i has-value

    DownloadsWeekly Downloads

    34,170,747

    Version

    2.0.2

    License

    MIT

    Unpacked Size

    10.7 kB

    Total Files

    4

    Last publish

    Collaborators

    • jonschlinkert