Ryan Cavanaugh

Using just `grammy` as a dependency: ```ts import { Bot } from "grammy"; export const teleBot = new Bot(""); teleBot.on(":animation", c => c); ```

Before ``` Identifiers: 57697 Symbols: 37871 Types: 9556 Instantiations: 240994 Memory used: 84999K Assignability cache size: 18439 Identity cache size: 128 Subtype cache size: 0 Strict subtype cache size: 0...

Basically stuck here: ```ts import { Filter, FilterQuery } from "grammy"; import { Context } from "grammy/out/context.js"; // Uncomment constraint to repro type MiddlewareFn = (ctx: C) => void; declare...

@ahejlsberg assigning to you since #57343 also was, but sounds like @Andarist might be working on it?

@ahejlsberg Try this? https://github.com/RyanCavanaugh/repro-58373 Relevant numbers on main ``` Files: 59 Lines of Library: 36690 Lines of Definitions: 13738 Identifiers: 53544 Symbols: 36350 Types: 532823 Instantiations: 235429 Memory used: 2693736K...

This should be a pretty easy one to isolate based on seeing which nodes/types/symbols are in the preceding stack frames.

I think what you should actually be seeing here is a circularity error

This isn't really a situation suitable for using `typeRoots` to solve. `typeRoots` tells TS that when resolving a type directive, each root should be consulted. Separately, if `types` is not...

Correct error for function expressions, but not function declarations - declarations won't infer `never`

Discussed and we don't want to make it untenable to, in the future, change the rules around function declaration return type inference. For example, it's maybe preferable that ```ts function...