Re: Duel reloaded: Duel.py (and a PrettyPrinter decorator)

Simon Marchi
2017-06-19T09:18:47Z

On 2017-06-19 11:03, Sergei Golubchik wrote:
> Hi,
>
> If you've never heard about Duel - it's an insanely cool data
> exploration language for gdb. Specifically designed to print out
> complex
> data structures in one command. Created as a public domain patch for
> gdb
> in 1993, but never got accepted for licensing reasons.
>
> Still, Duel is super-convenient, for example, to print the whole linked
> list one writes just
>
> (gdb) dl head-->next->val
>
> and to print field 'name' of every element in an array of structures,
> one writes
>
> (gdb) dl arr[..100].name

That's indeed very nice, I didn't know about it. The alternative of
these lines using only built-in gdb features would be to write a small
while loop, I guess. So I can see how this can be convenient.

> I've recently rewritten it in Python, so it doesn't need to be compiled
> with gdb anymore, one can load it run-time (e.g. from .gdbinit).
>
> Here it is: https://github.com/vuvova/gdb-tools
>
> This repository also includes a helper to simplify writing pretty
> printers. It removes all the boilerplate code that gdb requires, you
> only need to write the value-to-string function itself.

I really like using an annotation for declaring a pretty printer. I
wonder if we could (legally-wise and technically-wise) steal that idea
:).

Simon