Awesome
<p align="center"><a href="https://infernojs.org/" target="_blank"><img width="400" alt="Inferno" title="Inferno" src="https://user-images.githubusercontent.com/2021355/36073166-a47d4a8e-0f34-11e8-959c-860ea836d79d.png"></p> <p align="center"> <a href="https://www.npmjs.com/package/babel-plugin-inferno"><img src="https://img.shields.io/npm/dm/babel-plugin-inferno.svg" alt="Downloads"></a> <a href="https://www.npmjs.com/package/babel-plugin-inferno"><img src="https://img.shields.io/npm/v/babel-plugin-inferno.svg" alt="Version"></a> <a href="https://www.npmjs.com/package/babel-plugin-inferno"><img src="https://img.shields.io/npm/l/babel-plugin-inferno.svg" alt="License"></a> </p>InfernoJS Babel Plugin
Plugin for babel 6+ to enable JSX for Inferno
This plugin transforms JSX code in your projects to Inferno compatible virtual DOM.
It is recommended to use this plugin for compiling JSX for inferno. It is different to other JSX plugins, because it outputs highly optimized inferno specific createVNode
calls. This plugin also checks children shape during compilation stage to reduce overhead from runtime application.
How to install
npm i --save-dev babel-plugin-inferno
How to use
Add the plugin to your package.json
and update the plugin section in your .babelrc
file. Or if your Babel settings are located inside the package.json
- update the plugin section there.
It's important that you also include the babel-plugin-syntax-jsx
plugin.
Example on a .babelrc
file that will work with Inferno:
Make sure inferno plugin is added before babel module transformers
{
"presets": [ "es2015" ],
"plugins": [["babel-plugin-inferno", {"imports": true}]]
}
Examples
// Render a simple div
Inferno.render(<div></div>, container);
// Render a div with text
Inferno.render(<div>Hello world</div>, container);
// Render a div with a boolean attribute
Inferno.render(<div autoFocus='true' />, container);
Fragments
All of the following syntaxes are reserved for createFragment call
<>
<div>Foo</div>
<div>Bar</div>
</>
<Fragment>
<div>Foo</div>
<div>Bar</div>
</Fragment>
<Inferno.Fragment>
<div>Foo</div>
<div>Bar</div>
</Inferno.Fragment>
React.Fragment is also compiled to inferno createFragment call to ease project migration to Inferno https://github.com/infernojs/babel-plugin-inferno/issues/56.
Special flags
This plugin provides few special compile time flags that can be used to optimize an inferno application.
// ChildFlags:
<div $HasTextChildren /> - Children is rendered as pure text
<div $HasVNodeChildren /> - Children is another vNode (Element or Component)
<div $HasNonKeyedChildren /> - Children is always array without keys
<div $HasKeyedChildren /> - Children is array of vNodes having unique keys
<div $ChildFlag={expression} /> - This attribute is used for defining children shpae runtime. See inferno-vnode-flags (ChildFlags) for possibe values
// Functional flags
<div $ReCreate /> - This flag tells inferno to always remove and add the node. It can be used to replace key={Math.random()}
Flag called noNormalize
has been removed in v4, and is replaced by $HasVNodeChildren
Options
Change in v4:
Imports (boolean)
babel-plugin-inferno will automatically import the required methods from inferno library. There is no need to import inferno in every single JSX file. Only import the inferno specific code required by the application.
example:
import {render} from 'inferno'; // Just import what you need, (render in this case)
// The plugin will automatically import, createVNode
render(<div>1</div>, document.getElementById('root'));
You need to have support for ES6 modules for this to work. If you are using legacy build system or outdated version of webpack, you can revert this change by using imports: false
{
"presets": [ "es2015" ],
"plugins": [["inferno", {
"imports": false
}]]
}
Pragma
Each method that is used from inferno can be replaced by custom name.
pragma
(string) defaults to createVNode.
pragmaCreateComponentVNode
(string) defaults to createComponentVNode.
pragmaNormalizeProps
(string) defaults to normalizeProps.
pragmaTextVNode
(string) defaults to createTextVNode.
pragmaFragmentVNode
(string) defaults to createFragment.
{
"presets": [ "es2015" ],
"plugins": [["inferno", {
"imports": true,
"pragma": "",
"pragmaCreateComponentVNode": "",
"pragmaNormalizeProps": "",
"pragmaTextVNode": ""
}]]
}
Troubleshoot
You can verify babel-plugin-inferno
is used by looking at the compiled output.
This plugin does not generate calls to createElement
or h
, but instead it uses low level InfernoJS API
createVNode
, createComponentVNode
, createFragment
etc. If you see your JSX being transpiled into createElement
calls
its good indication that your babel configuration is not correct.