bug#61954: closed (30.0.50; [PATCH] Simplify structured commands in Eshell)

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Your message dated Thu, 16 Mar 2023 22:33:09 -0700
with message-id <e5000fd2-350a-eaea-c787-0551aa30ac23@gmail.com>
and subject line Re: bug#61954: 30.0.50; [PATCH] Simplify structured commands 
in Eshell
has caused the debbugs.gnu.org bug report #61954,
regarding 30.0.50; [PATCH] Simplify structured commands in Eshell
to be marked as done.

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--- Begin Message --- Subject: 30.0.50; [PATCH] Simplify structured commands in Eshell Date: Fri, 3 Mar 2023 23:28:46 -0800 Structured commands are just Eshell flow control commands, like 'if' and 'while'. These expected you to set 'eshell-test-body' and 'eshell-command-body' when implementing them, and were very hard to get right (see bug#12571 for example).

Instead, let's improve Eshell's iterative command evaluation some more so that you can write the implementations for these commands like normal. I think this is beneficial for two main reasons: a) it should get us closer to replacing Eshell's iterative evaluation with the CPS machinery in generator.el (bug#37635)[1], and b) third-parties should have an easier time writing their own fancy Eshell commands using the command-rewriting hooks.

Given that we have fairly thorough regression tests in Eshell now, I'm pretty confident that these patches don't break anything.

[1] I think I mentioned it elsewhere, but I'm hoping to make sure that when we do switch to the CPS machinery (or maybe to threads), it's just a drop-in replacement. That way, if there are problems, it should be easy to revert to the classic iterative evaluation code. Maybe we could even provide a defcustom for it just in case.

0001-Simplify-iteration-in-Eshell-for-loops.patch
Description: Text document

0002-Simplify-how-Eshell-s-iterative-evaluation-handles-i.patch
Description: Text document

0003-Simplify-usage-of-while-forms-in-Eshell-s-iterative-.patch
Description: Text document

--- End Message ---

> --- Begin Message ---
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> Subject: 
>
> Re: bug#61954: 30.0.50; [PATCH] Simplify structured commands in Eshell
>
>
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>
> Date: 
>
> Thu, 16 Mar 2023 22:33:09 -0700
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> On 3/3/2023 11:28 PM, Jim Porter wrote:
> > Structured commands are just Eshell flow control commands, like 'if' and 
> > 'while'. These expected you to set 'eshell-test-body' and 
> > 'eshell-command-body' when implementing them, and were very hard to get 
> > right (see bug#12571 for example).
> >
> > Instead, let's improve Eshell's iterative command evaluation some more 
> > so that you can write the implementations for these commands like 
> > normal.
>
> Since there haven't been any concerns about the patches themselves in 
> the last two weeks-ish, merging this now as 1565dbcae3 and closing the bug.
>
>
> --- End Message ---