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From: Michael Heerdegen <michael_heerdegen@web.de>
To: help-gnu-emacs@gnu.org
Subject: Re: Making ielm behave like a shell (getting to previous commands using the up-arrow key)
Date: Fri, 18 Dec 2020 10:01:14 +0100	[thread overview]
Message-ID: <87mtyb32ud.fsf@web.de> (raw)
In-Reply-To: X9w4hNQ/BPOK02wr@protected.rcdrun.com

Jean Louis <bugs@gnu.support> writes:

> That is how I learned it, instruction was somewhere on how to debug
> and I used to do it much in Common Lisp that way.

I must admit that I did not exhaustively understand how you proceed
because the code examples you had posted are broken (let binding syntax
broken).

> When you have
>
> (let ((some 1)
>       (more 2))
>
> How do you go about debugging such function?

Sometimes I insert `message' calls or something more sophisticated to
output values.  That's the simplest tool.

And then, sure, edebug and the built-in debugger - they allow inspecting
values live so there is no need to change the environment unless you
need to save a value for later inspection or reuse.

> Emacs has instrumenting of functions which can help and which is
> similar to setting each variable one by one with setq or setq-local

Similar, but actually much cooler since Edebug and the debugger have
real access to the debugged environment.

> What is your way of debugging it?

Depends on "it".  Apart from the above ways `debug-on-variable-change'
comes handy when you don't know where a binding changes.  Sometimes I'm
also using the tracer to trace variable bindings - one can implement
that easily using (the quite new) variable watchers.

Regards,

Michael.




  reply	other threads:[~2020-12-18  9:01 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-17  3:02 Making ielm behave like a shell (getting to previous commands using the up-arrow key) steve-humphreys
2020-12-17  3:34 ` Okam
2020-12-17  4:27 ` Michael Heerdegen
2020-12-17  4:44   ` steve-humphreys
2020-12-17  5:02     ` Michael Heerdegen
2020-12-17  5:17       ` steve-humphreys
2020-12-17  9:06         ` Jean Louis
2020-12-17  9:13           ` Jean Louis
2020-12-17 22:29           ` Michael Heerdegen
2020-12-18  5:05             ` Jean Louis
2020-12-18  9:01               ` Michael Heerdegen [this message]
2020-12-18 11:19                 ` Jean Louis
2020-12-18 17:14                   ` Drew Adams
2020-12-18 18:36                     ` Jean Louis
2020-12-18 19:11                       ` Drew Adams
2020-12-18 19:53                         ` Jean Louis
2020-12-18 21:15                           ` Drew Adams
2020-12-19  2:07                   ` Michael Heerdegen
2020-12-19  2:51                     ` Drew Adams
2020-12-18 11:28                 ` Jean Louis
2020-12-19  1:55                   ` Michael Heerdegen
2020-12-19  2:45                     ` Drew Adams
2020-12-19  1:57               ` Michael Heerdegen
2020-12-17  8:22   ` Joost Kremers
2020-12-18 10:20     ` Philip K.

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