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 with npm:
$ npm install --save has-valueBreaking changes in v2.0! See the release history for details.
consthas=require('has-value');console.log(has())//=> trueconsole.log(has('foo'))//=> trueWorks for:
- booleans
- functions
- numbers
- strings
- nulls
- object
- arrays
isEmpty
To do the opposite and test for empty values, do:
constisEmpty=(...args)=>!has(...args);console.log(has({foo: {bar: ['a']}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: [0]}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: [[[]]]}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: [[],[]]}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: []}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: true}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: false}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: newBuffer()}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: newBuffer('foo')}},'foo.bar'));//=> trueDates are always true.
console.log(has({foo: {bar: newDate()}},'foo.bar'));//=> trueReturns false if err.message is an empty string.
console.log(has({foo: {bar: newError()}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: newError('foo')}},'foo.bar'));//=> trueFunctions are always true.
console.log(has({foo: {bar: function(foo){}}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: function(){}}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: newMap()}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: newMap([['foo','bar']])}},'foo.bar'));//=> truenull 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'));//=> trueconsole.log(has({foo: {bar: {}}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: {a: 'a'}}}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: {foo: undefined}}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: {foo: null}}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: 1}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: 0}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: newRegExp()}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: newRegExp('foo')}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: newSet()}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: newSet(['foo','bar'])}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: 'a'}},'foo.bar'));//=> trueconsole.log(has({foo: {bar: ''}},'foo.bar'));//=> falseconsole.log(has({foo: {bar:}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: void0}},'foo.bar'));//=> falseconsole.log(has({foo: {bar: undefined}},'foo.bar'));//=> falseBreaking 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.
zeroalways returns truearraynow recurses, so that an array of empty arrays will returnfalsenullnow returns true
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 testBuilding 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 && verbYou 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
| Commits | Contributor |
|---|---|
| 32 | jonschlinkert |
| 2 | rmharrison |
| 1 | wtgtybhertgeghgtwtg |
Jon Schlinkert
Copyright © 2018, Jon Schlinkert. Released under the MIT License.
This file was generated by verb-generate-readme, v0.6.0, on March 03, 2018.