Prolog source layout

[JanWielemaker]

According to https://arxiv.org/pdf/0911.2899.pdf, the preferred layout for Prolog is to indent clause bodies with 4 and use spaces. I'm in favour of changing to this indentation and update the default settings for PceEmacs accordingly.

To facilitate this I wrote a Prolog program to convert the current layout reliably. I exploits the library prolog_colour to created a detailed annotated parse tree. How to make this available?

Possibly additional transformations:

• Move the cut (!) to its own line?

[triska]

Spaces: +1.

[edechter]

Move cut to its own line: +1

[edechter]

@JanWielemaker What is it exactly that you want to make available?

[JanWielemaker]

I probably want to make the re-indenter available for people who used the old SWI-Prolog layout and want to migrate to the new. Most likely as a pack.

[JanWielemaker]

This is all done. See https://github.com/JanWielemaker/reindent

[TeamSPoon]

This system preserves comments inlined with the code right?

…

On Mon, Jan 9, 2017 at 8:07 AM, Jan Wielemaker ***@***.***> wrote: Closed #186 <#186>. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#186 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAcgAc866hK_8mut5ZaMVuP4qYiYRwBEks5rQls_gaJpZM4LLh09> .

[JanWielemaker]

Yes. Well, it works quite ok provided you used the previous SWI-Prolog style. If rewrites that style
rather than creating an indentation from scratch.

[triska]

One example where the indentation of a comment broke:

SWI-Prolog/packages-ssl@6608d61#diff-08cee23742245590436e7e17427f44a2

Please see line 51 of client.pl in this commit.

[Anniepoo]

Jan, is this code available somewhere? Jan sez:

To facilitate this I wrote a Prolog program to convert the current layout reliably. I exploits the library prolog_colour to created a detailed annotated parse tree. How to make this available?Possibly additional transformations:

* Move the cut (!) to its own line?

[JanWielemaker]

See https://github.com/JanWielemaker/reindent
The main program is swi-indent.pl. Adjust paths and run swi-indent.pl --help for basic usage. By default it works in place, so make sure you have checked in your file prior to converting it so you can
go back.