Subject: bug#24617: 26.0.50; Handlers in `condition-case' should have programmatic access to the backtrace

From: Clément Pit--Claudel <[email-masked]>
Date: Tue, 4 Oct 2016 15:41:33 -0400

This sounds like a great idea!

As an aside, note that these things are not impossible; just tricky.  You just need to register your own debugger, then in that debugger function re-throw the error after recording the backtrace.  You also need to increment num-nonmacro-input-events from the debugger.

Clément.

On 2016-10-04 12:38, Philipp Stephani wrote:
> 
> Currently a handler in a `condition-case' form doesn't have access to
> the backtrace that was active when the signal was raised.  This makes
> many useful things impossible, such as re-raising signals or returning
> the backtrace to emacsclient.  I suggest either adding true exception
> objects (storing the error symbol, data, and backtrace), or at least
> providing a dynamic variable with the current backtrace.
> 
> 
> In GNU Emacs 26.0.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.8)
>  of 2016-10-04 built on localhost
> Repository revision: e2913dc880b9843bf69cf885270551bafeb46120
> Windowing system distributor 'The X.Org Foundation', version 11.0.11501000
> System Description:	Ubuntu 14.04 LTS
> 
> Recent messages:
> For information about GNU Emacs and the GNU system, type C-h C-a.
> 
> Configured using:
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> 
> Configured features:
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> TOOLKIT_SCROLL_BARS GTK3 X11 MODULES
> 
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>   locale-coding-system: utf-8-unix
> 
> Major mode: Lisp Interaction
> 
> Minor modes in effect:
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> 
> Load-path shadows:
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> 
> Features:
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> 
> Memory information:
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>