73 lines
2.1 KiB
Markdown
73 lines
2.1 KiB
Markdown
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# defined <sup>[![Version Badge][npm-version-svg]][package-url]</sup>
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[![github actions][actions-image]][actions-url]
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[![coverage][codecov-image]][codecov-url]
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[![License][license-image]][license-url]
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[![Downloads][downloads-image]][downloads-url]
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[![npm badge][npm-badge-png]][package-url]
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return the first argument that is `!== undefined`
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Most of the time when I chain together `||`s, I actually just want the first
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item that is not `undefined`, not the first non-falsy item.
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This module is like the defined-or (`//`) operator in perl 5.10+.
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# example
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``` js
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var defined = require('defined');
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var opts = { y : false, w : 4 };
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var x = defined(opts.x, opts.y, opts.w, 100);
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console.log(x);
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```
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```
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$ node example/defined.js
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false
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```
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The return value is `false` because `false` is the first item that is
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`!== undefined`.
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# methods
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``` js
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var defined = require('defined')
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```
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## var x = defined(a, b, c...)
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Return the first item in the argument list `a, b, c...` that is `!== undefined`.
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If all the items are `=== undefined`, return undefined.
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# install
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With [npm](https://npmjs.org) do:
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```
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npm install defined
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```
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# license
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MIT
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[package-url]: https://npmjs.org/package/defined
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[npm-version-svg]: https://versionbadg.es/inspect-js/defined.svg
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[deps-svg]: https://david-dm.org/inspect-js/defined.svg
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[deps-url]: https://david-dm.org/inspect-js/defined
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[dev-deps-svg]: https://david-dm.org/inspect-js/defined/dev-status.svg
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[dev-deps-url]: https://david-dm.org/inspect-js/defined#info=devDependencies
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[npm-badge-png]: https://nodei.co/npm/defined.png?downloads=true&stars=true
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[license-image]: https://img.shields.io/npm/l/defined.svg
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[license-url]: LICENSE
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[downloads-image]: https://img.shields.io/npm/dm/defined.svg
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[downloads-url]: https://npm-stat.com/charts.html?package=defined
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[codecov-image]: https://codecov.io/gh/inspect-js/defined/branch/main/graphs/badge.svg
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[codecov-url]: https://app.codecov.io/gh/inspect-js/defined/
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[actions-image]: https://img.shields.io/endpoint?url=https://github-actions-badge-u3jn4tfpocch.runkit.sh/inspect-js/defined
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[actions-url]: https://github.com/inspect-js/defined/actions
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