README
@shnhrrsn/babel-plugin-transform-isNil
Legacy
This has been updated for Babel 7 for backwards compatibilty of existing code, however new code should migrate to the chaining operator: @babel/plugin-proposal-optional-chaining
Forked from MaxMEllon
This was forked from MaxMEllon/babel-plugin-transform-isNil, which has since been deprecated, and updated to work with Babel 7.
@shnhrrsn/babel-plugin-transform-isNil
About
I like Existential Operator in CoffeeScript.
CoffeeScript can be written as follows:
hoge?
Become to JavaScript
hoge == null
Same meaning
hoge === null || hoge === undefined
I want to do the same thing in JavaScript.
Installation
$ npm install --save @shnhrrsn/babel-plugin-transform-isNil
Example
In
if (foo.isNil) {
console.log('foo is null or undefined');
}
Out
if (foo === null || foo === undefined) {
console.log('foo is null or undefined');
}
In
if (hoge.poge.isNil && foo.bar.isNil) {
console.log('hoge.poge and foo.bar is null or undefined');
}
Out
if ((hoge.poge === null || hoge.poge === undefined) && (foo.bar === null || foo.bar === undefined)) {
console.log('hoge.poge and foo.bar is null or undefined');
}
In
if (hoge.poge().isNil) {
console.log('returned value of hoge.poge() function is null or undefined');
}
Out
if (hoge.poge() === null || hoge.poge() === undefined) {
console.log('returned value of hoge.poge() function is null or undefined');
}
In
if (hoge.poge(hoge).isNil) {
console.log('returned value of hoge.poge() function is null or undefined');
}
Out
if (hoge.poge(hoge) === null || hoge.poge(hoge) === undefined) {
console.log('returned value of hoge.poge() function is null or undefined');
}
Usage
Via .babelrc
{
"plugins": ["@shnhrrsn/plugin-transform-isNil"]
}
Development
Requirement global
- Node v4 or above
$ git clone https://github.com/shnhrrsn/babel-plugin-transform-isNil
$ cd babel-plugin-transform-isNil
$ npm install
$ npm test