@babel/plugin-transform-react-jsx
NOTE: This plugin is included in
@babel/preset-react
Example
React Automatic Runtime
Automatic runtime is a feature added in v7.9.0
. With this runtime enabled, the functions that JSX compiles to will be imported automatically.
In
const profile = (
<div>
<img src="avatar.png" className="profile" />
<h3>{[user.firstName, user.lastName].join(" ")}</h3>
</div>
);
Out
import { jsx as _jsx } from "react/jsx-runtime";
import { jsxs as _jsxs } from "react/jsx-runtime";
const profile = _jsxs("div", {
children: [
_jsx("img", {
src: "avatar.png",
className: "profile",
}),
_jsx("h3", {
children: [user.firstName, user.lastName].join(" "),
}),
],
});
Customizing the Automatic Runtime Import
In
/** @jsxImportSource custom-jsx-library */
const profile = (
<div>
<img src="avatar.png" className="profile" />
<h3>{[user.firstName, user.lastName].join(" ")}</h3>
</div>
);
Out
import { jsx as _jsx } from "custom-jsx-library/jsx-runtime";
import { jsxs as _jsxs } from "custom-jsx-library/jsx-runtime";
const profile = _jsxs("div", {
children: [
_jsx("img", {
src: "avatar.png",
className: "profile",
}),
_jsx("h3", {
children: [user.firstName, user.lastName].join(" "),
}),
],
});
In
/** @jsxRuntime classic */
const profile = (
<div>
<img src="avatar.png" className="profile" />
<h3>{[user.firstName, user.lastName].join(" ")}</h3>
</div>
);
Out
const profile = React.createElement(
"div",
null,
React.createElement("img", { src: "avatar.png", className: "profile" }),
React.createElement("h3", null, [user.firstName, user.lastName].join(" "))
);
React Classic Runtime
If you do not want (or cannot use) auto importing, you can use the classic runtime, which is the default behavior for v7 and prior.
In
const profile = (
<div>
<img src="avatar.png" className="profile" />
<h3>{[user.firstName, user.lastName].join(" ")}</h3>
</div>
);
Out
const profile = React.createElement(
"div",
null,
React.createElement("img", { src: "avatar.png", className: "profile" }),
React.createElement("h3", null, [user.firstName, user.lastName].join(" "))
);
Customizing the Classic Runtime Import
In
/** @jsx Preact.h */
import Preact from "preact";
const profile = (
<div>
<img src="avatar.png" className="profile" />
<h3>{[user.firstName, user.lastName].join(" ")}</h3>
</div>
);
Out
/** @jsx Preact.h */
import Preact from "preact";
const profile = Preact.h(
"div",
null,
Preact.h("img", { src: "avatar.png", className: "profile" }),
Preact.h("h3", null, [user.firstName, user.lastName].join(" "))
);
Fragments
Fragments are a feature available in React 16.2.0+.
React
In
const descriptions = items.map(item => (
<>
<dt>{item.name}</dt>
<dd>{item.value}</dd>
</>
));
Out
const descriptions = items.map(item =>
React.createElement(
React.Fragment,
null,
React.createElement("dt", null, item.name),
React.createElement("dd", null, item.value)
)
);
Customizing with the Classic Runtime
In
/** @jsx Preact.h */
/** @jsxFrag Preact.Fragment */
import Preact from "preact";
var descriptions = items.map(item => (
<>
<dt>{item.name}</dt>
<dd>{item.value}</dd>
</>
));
Out
/** @jsx Preact.h */
/** @jsxFrag Preact.Fragment */
import Preact from "preact";
var descriptions = items.map(item =>
Preact.h(
Preact.Fragment,
null,
Preact.h("dt", null, item.name),
Preact.h("dd", null, item.value)
)
);
Note that if a custom pragma is specified, then a custom fragment pragma must also be specified if the fragment sytnax <></>
is used. Otherwise, an error will be thrown.
Installation
npm install --save-dev @babel/plugin-transform-react-jsx
Usage
With a configuration file (Recommended)
Without options:
{
"plugins": ["@babel/plugin-transform-react-jsx"]
}
With options:
{
"plugins": [
[
"@babel/plugin-transform-react-jsx",
{
"throwIfNamespace": false, // defaults to true
"runtime": "automatic", // defaults to classic
"importSource": "custom-jsx-library" // defaults to react
}
]
]
}
Via CLI
babel --plugins @babel/plugin-transform-react-jsx script.js
Via Node API
require("@babel/core").transformSync("code", {
plugins: ["@babel/plugin-transform-react-jsx"],
});
Options
Both Runtimes
throwIfNamespace
boolean
, defaults to true
.
Toggles whether or not to throw an error if an XML namespaced tag name is used. For example:
<f:image />
Though the JSX spec allows this, it is disabled by default since React's JSX does not currently have support for it.
You can read more about configuring plugin options here
runtime
classic | automatic
, defaults to classic
Added in: v7.9.0
Decides which runtime to use.
automatic
auto imports the functions that JSX transpiles to. classic
does not automatically import anything.
React Automatic Runtime
importSource
string
, defaults to react
.
Added in: v7.9.0
Replaces the import source when importing functions.
React Classic Runtime
pragma
string
, defaults to React.createElement
.
Replace the function used when compiling JSX expressions.
Note that the @jsx React.DOM
pragma has been deprecated as of React v0.12
pragmaFrag
string
, defaults to React.Fragment
.
Replace the component used when compiling JSX fragments.
useBuiltIns
boolean
, defaults to false
.
When spreading props, use Object.assign
directly instead of Babel's extend helper.
useSpread
boolean
, defaults to false
.
When spreading props, use inline object with spread elements directly instead of Babel's extend helper or Object.assign
.