@babel/plugin-proposal-nullish-coalescing-operator
NOTE: This plugin is included in
@babel/preset-env
, in ES2020
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
.
⚠️ Consider migrating to the top level
noDocumentAll
assumption.
// babel.config.json { "assumptions": { "noDocumentAll": true } }
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