Re: [PATCH 1-2/2] Emacsy buffer.scm fixes, opt argument for `switch-to-buffer'

[Amar Singh]

On June 26, 2019 6:05:39 PM GMT+05:30, Jan Nieuwenhuizen <address@hidden> wrote:
>Amar Singh writes:
>
>> Emacsy's `set-buffer!' does not seem to work
>
>What are you trying to achieve?  Set-buffer! is used eg in with-buffer
>
>--8<---------------cut here---------------start------------->8---
>(define-syntax with-buffer
>  (syntax-rules ()
>    ((with-buffer buffer e ...)
>     (let ((old-buffer (current-buffer))
>           (result *unspecified*))
>       (in-out-guard
>        (lambda () (set-buffer! buffer))
>        (lambda () e ...)
>        (lambda () (set-buffer! old-buffer)))))))
>--8<---------------cut here---------------end--------------->8---
>
>and works fine.  You don't want to use it interactively.
>
>> and `switch-to-buffer'
>> does a bit more than just switch to the given buffer(it also
>re-orders
>> the buffer-stack).
>
>Yes, it also calls buffer-exit and enter hooks; this is exactly what
>Emacs does.
>
>> Maybe an optional argument to `switch-to-buffer'
>> should be provided if the user also wants to set the current buffer
>as
>> most recently used in `buffer-stack'. WDYT?
>
>> Both, resetting buffer order, and not touching it are useful
>behaviours.
>
>I don't think that's what we want, I'm imagining this helps you to
>achieve something so I'm curious what you want to do?
>
>> From da20cae843753991422478598da193b5a9f6b35d Mon Sep 17 00:00:00
>2001
>> From: Amar Singh <address@hidden>
>> Date: Mon, 24 Jun 2019 02:22:48 +0530
>> Subject: [PATCH 1/2] buffer.scm fixes: other-buffer, next-buffer
>
>LGTM, applied.
>
>> From 1015052f51209adc766d6e1ff4f602c5a0f9f67c Mon Sep 17 00:00:00
>2001
>> From: Amar Singh <address@hidden>
>> Date: Tue, 25 Jun 2019 19:44:08 +0530
>> Subject: [PATCH 2/2] buffer.scm: `switch-to-buffer' takes additional
>argument
>>  recall?
>
>Not yet, let's see.
>
>> -        (mru-recall! buffer-stack buffer)
>> +        (if recall? (mru-recall! buffer-stack buffer))
>
>(please use `when' for an if without else clause).
>
>janneke

>I don't think that's what we want, I'm imagining this helps you to
>achieve something so I'm curious what you want to do?

We want to have commands like next-buffer, previous-buffer and other-buffer 
with Emacs-like semantics.

Imagine we have buffers:
gnu.org 127.0.0.1 Messages

buffer-next!: gnu.org 127.0.0.1 Messages (assume it moves through buffers in 
this direction)

then,
buffer-previous!: gnu.org Messages 127.0.0.1

but can you guess what happens when interactive versions of buffer-next! and 
buffer-previous! are called?

next-buffer: gnu.org 127.0.0.1 gnu.org (keeps cycling between the two)
prev-buffer: gnu.org Messages 127.0.0.1

this has to do with the fact that switch-to-buffer will call mru-recall!. This 
behaviour of switch-to-buffer is unexpected and should be optional i think.

but we may also want to have(Emacs-like other-buffer)
other-buffer: gnu.org 127.0.0.1 gnu.org

other-buffer should look like something: (sry should have included this in the 
patch as well)

(mru-next! buffer-stack incr)
(switch-to-buffer (mru-ref buffer-stack) t)

wdyt?
Amar Singh<address@hidden>
----------------
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