What is the current state of debugger support for OCaml? I am aware of ocamldebug but every time I’m trying to use it I feel thrown back to 2000 where it essentially existed in the same form (and still has no command line editing built in). Despite the powerful concept of time traveling, it does not…

I looked at it but also haven’t used it. I agree that is looks nice and it would provide a much nicer interface. It seems to depend on compiler internals, based on currently raised issues.

I agree that debugging in OCaml seems to be stuck in time. This is extremely unfortunate because it is able to do time traveling (as you mention) which is something that many other languages still cannot boast. ocamldebug does not work properly when there is more than 1 OS thread As types are er…

As types are erased during compile time in OCaml, it can be difficult to debug polymorphic functions. I am not sure if this would be away around this: a compiler flag that disregards hiding types - similar to removing all MLI files for debugging. The strong information hiding becomes a disadvanta…

I think it is likely to be very hard to prevent erasure of types. The whole runtime representation of ocaml data types might need to be changed and new fields to hold type information added?

[image] lindig: a compiler flag that disregards hiding types - similar to removing all MLI files for debugging. Curious – What flag is this?

It does not exist. But I believe the debugger has more visibility into values if you remove MLI files that would otherwise restrict the view. Given that MLI files are optional and don’t contain information not present in the corresponding ML file, I could imagine that such a flag could help. Pure sp…

[image] sid: This is extremely unfortunate because it is able to do time traveling (as you mention) which is something that many other languages still cannot boast. I agree that time travel debugging is useful, but is this something really unique to OCaml? when I last tried to read through th…

[image] sid: I think it is likely to be very hard to prevent erasure of types. The whole runtime representation of ocaml data types might need to be changed and new fields to hold type information added? One thing I’ve repeatedly heard on these forums is that the OCaml compiler (if we ignore …

Going from byte code back to Typed AST is most likely a hard problem. This is basically doing disassembly of sorts. There is a loss of information so I don’t think full reconstruction is possible. Perhaps if more debugging information was embedded with the bytecode (so ensuring no important informat…

Debugger support for OCaml

Ecosystem

linoscope December 27, 2021, 3:31pm 2

Have you taken a look at ocamlearlybird (github, announcement)? I have never used it myself, but based on the demo it seems pretty nice.

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Debugger support for OCaml

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