algorithms/node_modules/has-value

has-value

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

Install

Install with npm:

$ npm install --save has-value

Works for:

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

Usage

Works with property values (supports object-path notation, like foo.bar) or a single value:

var hasValue = require('has-value');

hasValue('foo');
hasValue({foo: 'bar'}, 'foo');
hasValue({a: {b: {c: 'foo'}}}, 'a.b.c');
//=> true

hasValue('');
hasValue({foo: ''}, 'foo');
//=> false

hasValue(0);
hasValue(1);
hasValue({foo: 0}, 'foo');
hasValue({foo: 1}, 'foo');
hasValue({foo: null}, 'foo');
hasValue({foo: {bar: 'a'}}}, 'foo');
hasValue({foo: {bar: 'a'}}}, 'foo.bar');
//=> true

hasValue({foo: {}}}, 'foo');
hasValue({foo: {bar: {}}}}, 'foo.bar');
hasValue({foo: undefined}, 'foo');
//=> false

hasValue([]);
hasValue([[]]);
hasValue([[], []]);
hasValue([undefined]);
hasValue({foo: []}, 'foo');
//=> false

hasValue([0]);
hasValue([null]);
hasValue(['foo']);
hasValue({foo: ['a']}, 'foo');
//=> true

hasValue(function() {})
hasValue(function(foo) {})
hasValue({foo: function(foo) {}}, 'foo'); 
hasValue({foo: function() {}}, 'foo');
//=> true

hasValue(true);
hasValue(false);
hasValue({foo: true}, 'foo');
hasValue({foo: false}, 'foo');
//=> true

isEmpty

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

function isEmpty(o) {
  return !hasValue.apply(hasValue, arguments);
}

Release history

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

Related projects

• define-property: Define a non-enumerable property on an object. | homepage
• get-value: Use property paths (a.b.c) to get a nested value from an object. | homepage to get a nested value from an object.")
• set-value: Create nested values and any intermediaries using dot notation ('a.b.c') paths. | homepage paths.")
• unset-value: Delete nested properties from an object using dot notation. | homepage

Contributing

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

Contributors

| Commits | Contributor | | --- | --- | | 17 | jonschlinkert | | 2 | rmharrison |

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

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

Author

Jon Schlinkert

• github/jonschlinkert
• twitter/jonschlinkert

License

Copyright © 2017, Jon Schlinkert. Released under the MIT License.

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This file was generated by verb-generate-readme, v0.6.0, on May 19, 2017.