babel-plugin-transform-remove-undefined

For variable assignments, this removes rvals that evaluate to undefined
(vars in functions only).
For functions, this removes return arguments that evaluate to undefined.

Example

In

``javascript
let a = void 0;
function foo() {
var b = undefined;
return undefined;
}
`

Out

`javascript
let a;
function foo() {
var b;
return;
}
`

Installation

`sh
npm install babel-plugin-transform-remove-undefined --save-dev
`

Usage

$3

.babelrc

`json
{
"plugins": ["babel-plugin-transform-remove-undefined"]
}
`

$3

`sh
babel --plugins babel-plugin-transform-remove-undefined script.js
`

$3

`javascript
require("@babel/core").transform("code", {
plugins: ["babel-plugin-transform-remove-undefined"]
});
`

Options

+ tdz` - Detect usages before declaration/initialization in let/const(throws) and var(void 0)