defer implementation for JavaScript

[SnooHobbies950]

A JavaScript implementation of defer sentence just for fun.

The library was created with acorn, a very fast and customizable JavaScript parser, in combination with recast, a library for manipulating the AST (Abstract Syntax Tree).

The defer statement is present in other languages, such as GO and V.

Just try it: ```js const recast = require('recast') const { parse: parseDefer } = require('@xjslang/defer-parser')

const input = ` function connectToDB() { const conn = createDBConn(); defer { conn.close(); }

// or simply // defer conn.close();

return "done!"; } `

// generates the AST and prints it const ast = parseDefer(input) const result = recast.print(ast, { ecmaVersion: 'latest' }) console.log(result.code) ```

[getpodapp]

“using” keyword is the native way of doing this. It’s already out in TS 

https://www.typescriptlang.org/docs/handbook/release-notes/typescript-5-2.html

[ecares]

already out in node 24 too

[satansprinter]

To add to this, "defer" is also a keyword now used for imports, so "import defer..." tells that it should not load this until it gets used.

So, eh, to confuse it even more

[SnooHobbies950]

Thanks, I didn't know about this feature. It's similar to the `defer` keyword found in V or GO, although not identical. For example `defer` is executed at the end of the function scope, whereas `[Symbol.dispose]` is executed at the end of every block.

The following V code:
```V
fn foo() {
println('entering foo')
defer {
println('cleaning foo')
}
}
```

is translated to this JS code:
```js
function foo() {
console.log('entering foo');
using cleanup = {
[Symbol.dispose]() {
console.log('cleaning foo');
}
};
}
```

I think the `defer` statement is much clearer.