Re: [PATCH v1] gdb/DAP Introduce new methods to to Pretty Printers

[Tom Tromey <tromey@adacore.com>]

>>>>> "Matt" == Matt Rice <ratmice@gmail.com> writes:

Matt> On Thu, Jul 13, 2023 at 8:38 PM Tom Tromey via Gdb-patches
Matt> <gdb-patches@sourceware.org> wrote:
>> 
>> Maybe one way out would be to define a new way to do pretty-printers,
>> with a compatibility shim.

Matt> FWIW, there has been a bit of spit-balling within the rust community
Matt> about leveraging Debug trait implementations
Matt> within pretty printers, where what seemed to me like the obvious way
Matt> to leverage these was to compile Debug impls to wasm,
Matt> and write a python wrapper which calls into the wasm.  I haven't
Matt> thought or looked into it too much to have considered any hurdles of
Matt> this approach really, but it would be nice if languages with wasm
Matt> toolchains could define/compile pretty printers in their own language,
Matt> since often they already exist for the purpose of runtime logging...
Matt> Seemed worth bringing up if we're spit-balling here too.

Ages ago I looked into this a little, the idea being to compile selected
functions to Python using the gdb API.  In the end though it seemed too
hard for the value it would deliver.

Anyway, the wasm approach seems fine -- they solved all the toolchain
problems, which is nice.  The main issue is that, IIUC, debug traits
just emit a string representation -- but IMO the debugger really wants a
more key-value / array-like representation.

This seems like something that could be implemented "on the side", like
the way that gdb-natvis exists.

Tom