@babel/plugin-proposal-nullish-coalescing-operator
NOTE: This plugin is included in
@babel/preset-env
Example
In
var foo = object.foo ?? "default";
Out
var _object$foo;
var foo =
(_object$foo = object.foo) !== null && _object$foo !== void 0
? _object$foo
: "default";
NOTE: We cannot use
!= null
here becausedocument.all == null
anddocument.all
has been deemed not "nullish".
Installation
npm install --save-dev @babel/plugin-proposal-nullish-coalescing-operator
Usage
With a configuration file (Recommended)
{
"plugins": ["@babel/plugin-proposal-nullish-coalescing-operator"]
}
Via CLI
babel --plugins @babel/plugin-proposal-nullish-coalescing-operator script.js
Via Node API
require("@babel/core").transformSync("code", {
plugins: ["@babel/plugin-proposal-nullish-coalescing-operator"],
});
Options
loose
boolean
, defaults to false
.
When true
, this transform will pretend document.all
does not exist,
and perform loose equality checks with null
instead of strict equality checks
against both null
and undefined
.
Example
In
var foo = object.foo ?? "default";
Out
var _object$foo;
var foo = (_object$foo = object.foo) != null ? _object$foo : "default";
You can read more about configuring plugin options here