Effect.Shallow(3)

✨ NAME ✨

omg hi bestie 💖 welcome to the Effect.Shallow(3) page. The official NAME section is literally “no description” — iconic, mysterious, zero notes. But it’s all about shallow effect handlers and delimited continuations, and we’re gonna get you comfy with it. 🦋

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🧩 Module 🧩

Module Effect.Shallow

📚 Documentation 📚

🧚 Module Shallow

Module Shallow
 : sig end

Okay so here’s the whole Shallow module vibe — it’s giving “small but powerful,” and every type and val below is exactly what’s on the menu. 💅

• type ('a, 'b) continuation — bestie, this is a delimited continuation that expects a 'a value and returns a 'b value. lowkey main character energy: it’s waiting for a value, then it gives you a result. 🎀
• val fiber : ('a -> 'b) -> ('a, 'b) continuation — fiber f constructs a continuation that runs the computation f. slay. ✨
• type ('a, 'b) handler = { ... } — this is the handler record with three fields. not me being obsessed with a record, but here we are:

type ('a, 'b) handler = {
 retc : 'a -> 'b ;
 exnc : exn -> 'b ;
 effc : 'c. 'c Effect.t -> (('c, 'a) continuation -> 'b) option ;
 }

So: retc is the value handler, exnc handles exceptions, and effc handles the effects performed by the computation enclosed by the handler. periodt. 🫶

• val continue_with : ('c, 'a) continuation -> 'c -> ('a, 'b) handler -> 'b — continue_with k v h resumes the continuation k with value v with the handler h. 💖

Raises Continuation_already_resumed if the continuation has already been resumed. (so don’t double-resume, bestie, it’s not that kind of party 😭)

• val discontinue_with : ('c, 'a) continuation -> exn -> ('a, 'b) handler -> 'b — discontinue_with k e h resumes the continuation k by raising the exception e with the handler h. dramatic? yes. valid? also yes. 💀

Raises Continuation_already_resumed if the continuation has already been resumed.

• val discontinue_with_backtrace : ('a, 'b) continuation -> exn -> Printexc.raw_backtrace -> ('b, 'c) handler -> 'c — the doc describes it as discontinue_with k e bt h: it resumes the continuation k by raising the exception e with the handler h, using the raw backtrace bt as the origin of the exception. backtrace lore fr fr. 🔥

Raises Continuation_already_resumed if the continuation has already been resumed.

• val get_callstack : ('a, 'b) continuation -> int -> Printexc.raw_backtrace — get_callstack c n returns a description of the top of the call stack on the continuation c, with at most n entries. peek at the stack, but make it delimited. ⭐

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mwah 💋 — OCamldoc, 2026-06-22. byeee 👑