Too large modules

[jjangga0214]

Suggestion

Some modules are too large.

For example, src/compiler/checker.ts has 42,797 lines, in one single file.

(Some other modules have a few thousand lines, though that MAY be viewed as suitable in some cases. )

I think that's too much and not so easy to organize and grasp, especially for contributors.

Even several IDE(e.g. vscode) extensions don't properly work for it.

Thus I suggest splitting the logic into more files.

🔍 Search Terms

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✅ Viability Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

[MartinJohns]

Related: #35210 / #27891.

[RyanCavanaugh]

The file is this large because it's faster to have more functions in the same closure when sharing state.

[jjangga0214]

@RyanCavanaugh

But 42,797 lines are insane!
I guess there are other solutions?

1. Generate the closure as a single file: Like bundling!
   or
2. Change language: Having to optimize THAT MUCH(e.g. 42,797 lines) may mean the initial choice of language was fundamentally wrong. We should consider porting to faster languages (e.g. C++, Rust, Go, etc).

Can you reopen the issue? Or Creating a new issue for the solutions would be better?

[RyanCavanaugh]

We (the engineers on this team) all work in this file every day. If it were truly a problem that needed solving through some complex external tooling, we would have done it by now. It's not. The prioritization of our finite resources is not going to hinge on your personal distaste of a line count.