Simplify pipeline parsing with using declarations

[nicolo-ribaudo]

Q	A
Fixed Issues?
Patch: Bug Fix?
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

This is mostly an experiment to see how using declarations can simplify our state management in the parser (currently we have a lot of intermediate functions to hide try/finally statements).

I also have other drafts to see how migrating to using looks like: https://github.com/nicolo-ribaudo/babel/pull/10/files?w=1, https://github.com/nicolo-ribaudo/babel/pull/11/files?w=1

I'll also open a PR to remove the F# and smart proposals in babel 8, since they are unfortunately not being pursued anymore.

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/56142/

[liuxingbaoyu]

I personally tend to use using outside of parser/generator and other places where performance is more important. I am worried that this will affect a little performance.

[nicolo-ribaudo]

I will try to do some benchmarks

[nicolo-ribaudo]

This PR introduces a performance regression indeed, we should not merge it until I figure out how to solve it.

However, it also looks like we currently have a big perf regression on main 🤔

This PR:

➜ node ./benchmark/babel-parser/real-case/bench.mjs
current 4 jquery 3.6: 13.21 ops/sec ±1.75% (76ms)
baseline 4 jquery 3.6: 22.71 ops/sec ±2.19% (44ms)
current 4 jquery 3.6: 13.32 ops/sec ±1.58% (75ms)
baseline 4 jquery 3.6: 22.31 ops/sec ±2.49% (45ms)

main:

➜ node ./benchmark/babel-parser/real-case/bench.mjs
current 4 jquery 3.6: 15.07 ops/sec ±1.91% (66ms)
baseline 4 jquery 3.6: 23.62 ops/sec ±2.25% (42ms)
current 4 jquery 3.6: 14.88 ops/sec ±2.2% (67ms)
baseline 4 jquery 3.6: 24.06 ops/sec ±2.07% (42ms)

where baseline is @babel/parser@7.23.6, and I'm compiling as CJS with make build.

[liuxingbaoyu]

Please use make prepublish-build. :)

To be honest, I'm surprised that this is reflected in real-case, or even that this syntax is not included in the example.

[nicolo-ribaudo]

To be honest, I'm surprised that this is reflected in real-case, or even that this syntax is not included in the example.

It's because parsing for the smart pipeline needs to reset context every time we enter a block, so it's all over the place.