changing visuals of code in emacs

changing visuals of code in emacs

[Andrei Alexandrescu]

Hello,


I'd like to change code visuals for the D programming language as 
follows. I'd like the construct:

Symbol!(balanced_parens)

to be visualized as:

Symbol«balanced_parens»

The chevrons should appear electrically when I type the closing ")". 
Note that balanced_parens could in turn nested use of "!()", as in 
A!(B!(C)), and they should all be paired using chevrons. The underlying 
file should not contain the chevrons, just the ASCII representation 
using "!(" and ")".

I haven't done much elisp programming beyond the common .emacs 
configuration tricks, so I don't know where to start. A few searches 
suggested that overlays may be what I'm looking for... any ideas and 
pointers? Thank you.


Andrei

Re: changing visuals of code in emacs

[Pascal J. Bourguignon]

Andrei Alexandrescu <SeeWebsiteForEmail@erdani.org> writes:

> Hello,
>
>
> I'd like to change code visuals for the D programming language as
> follows. I'd like the construct:
>
> Symbol!(balanced_parens)
>
> to be visualized as:
>
> Symbol«balanced_parens»
>
> The chevrons should appear electrically when I type the closing
> ")". Note that balanced_parens could in turn nested use of "!()", as
> in A!(B!(C)), and they should all be paired using chevrons. The
> underlying file should not contain the chevrons, just the ASCII
> representation using "!(" and ")".
>
> I haven't done much elisp programming beyond the common .emacs
> configuration tricks, so I don't know where to start. A few searches
> suggested that overlays may be what I'm looking for... any ideas and
> pointers? Thank you.

If you didn't ask for recursion, this could have be done with
font-locking.

(font-lock-add-keywords nil
  '(("\\(!(\\)[^()]*\\()\\)" 
     0 (progn
         (compose-region (match-beginning 1) (match-end 1) ?« 'decompose-region)
         (compose-region (match-beginning 2) (match-end 2) ?» 'decompose-region)
         nil))))

But since this uses regular expressions, it won't work for recursive
!(...).


You can still use compose-region, but you'll have to implement the
parsing yourself.  Perhaps this could be hooked on the code doing the
parenthesis balancing?


-- 
__Pascal Bourguignon__                     http://www.informatimago.com/
You never feed me.
Perhaps I'll sleep on your face.
That will sure show you.

Re: changing visuals of code in emacs

[Andrei Alexandrescu]

Pascal J. Bourguignon wrote:
> Andrei Alexandrescu <SeeWebsiteForEmail@erdani.org> writes:
> 
>> Hello,
>>
>>
>> I'd like to change code visuals for the D programming language as
>> follows. I'd like the construct:
>>
>> Symbol!(balanced_parens)
>>
>> to be visualized as:
>>
>> Symbol«balanced_parens»
>>
>> The chevrons should appear electrically when I type the closing
>> ")". Note that balanced_parens could in turn nested use of "!()", as
>> in A!(B!(C)), and they should all be paired using chevrons. The
>> underlying file should not contain the chevrons, just the ASCII
>> representation using "!(" and ")".
>>
>> I haven't done much elisp programming beyond the common .emacs
>> configuration tricks, so I don't know where to start. A few searches
>> suggested that overlays may be what I'm looking for... any ideas and
>> pointers? Thank you.
> 
> If you didn't ask for recursion, this could have be done with
> font-locking.
> 
> (font-lock-add-keywords nil
>   '(("\\(!(\\)[^()]*\\()\\)" 
>      0 (progn
>          (compose-region (match-beginning 1) (match-end 1) ?« 'decompose-region)
>          (compose-region (match-beginning 2) (match-end 2) ?» 'decompose-region)
>          nil))))
> 
> But since this uses regular expressions, it won't work for recursive
> !(...).
> 
> 
> You can still use compose-region, but you'll have to implement the
> parsing yourself.  Perhaps this could be hooked on the code doing the
> parenthesis balancing?

I think I'd be happy with a nonrecursive region to get my feet wet. How 
do I use your font-lock-add-keywords code? I added it to both my .emacs 
and my d-mode.el file, to no avail.

Thank you,

Andrei

Re: changing visuals of code in emacs

[Pascal J. Bourguignon]

Andrei Alexandrescu <SeeWebsiteForEmail@erdani.org> writes:

> Pascal J. Bourguignon wrote:
>> Andrei Alexandrescu <SeeWebsiteForEmail@erdani.org> writes:
>> 
>>> Hello,
>>>
>>>
>>> I'd like to change code visuals for the D programming language as
>>> follows. I'd like the construct:
>>>
>>> Symbol!(balanced_parens)
>>>
>>> to be visualized as:
>>>
>>> Symbol«balanced_parens»
>>>
>>> The chevrons should appear electrically when I type the closing
>>> ")". Note that balanced_parens could in turn nested use of "!()", as
>>> in A!(B!(C)), and they should all be paired using chevrons. The
>>> underlying file should not contain the chevrons, just the ASCII
>>> representation using "!(" and ")".
>>>
>>> I haven't done much elisp programming beyond the common .emacs
>>> configuration tricks, so I don't know where to start. A few searches
>>> suggested that overlays may be what I'm looking for... any ideas and
>>> pointers? Thank you.
>> If you didn't ask for recursion, this could have be done with
>> font-locking.
>> (font-lock-add-keywords nil
>>   '(("\\(!(\\)[^()]*\\()\\)"      0 (progn
>>          (compose-region (match-beginning 1) (match-end 1) ?« 'decompose-region)
>>          (compose-region (match-beginning 2) (match-end 2) ?» 'decompose-region)
>>          nil))))
>> But since this uses regular expressions, it won't work for recursive
>> !(...).
>> You can still use compose-region, but you'll have to implement the
>> parsing yourself.  Perhaps this could be hooked on the code doing the
>> parenthesis balancing?
>
> I think I'd be happy with a nonrecursive region to get my feet
> wet. How do I use your font-lock-add-keywords code? I added it to both
> my .emacs and my d-mode.el file, to no avail.

You could run it from a d-mode-hook if it exists, ensuring that
font-lock-mode is enabled.

(add-hook 'd-mode-hook 
          (lambda () 
            (font-lock-add-keywords nil
              '(("\\(!(\\)[^()]*\\()\\)"      0 (progn
                     (compose-region (match-beginning 1) (match-end 1) ?« 'decompose-region)
                     (compose-region (match-beginning 2) (match-end 2) ?» 'decompose-region)
                     nil))))
            (font-lock-mode 1)))

-- 
__Pascal Bourguignon__                     http://www.informatimago.com/

Pour moi, la grande question n'a jamais été: «Qui suis-je? Où vais-je?» 
comme l'a formulé si adroitement notre ami Pascal, mais plutôt: 
«Comment vais-je m'en tirer?» -- Jean Yanne

Re: changing visuals of code in emacs

[Andrei Alexandrescu]

Pascal J. Bourguignon wrote:
> Andrei Alexandrescu <SeeWebsiteForEmail@erdani.org> writes:
> 
>> Pascal J. Bourguignon wrote:
>>> Andrei Alexandrescu <SeeWebsiteForEmail@erdani.org> writes:
>>>
>>>> Hello,
>>>>
>>>>
>>>> I'd like to change code visuals for the D programming language as
>>>> follows. I'd like the construct:
>>>>
>>>> Symbol!(balanced_parens)
>>>>
>>>> to be visualized as:
>>>>
>>>> Symbol«balanced_parens»
>>>>
>>>> The chevrons should appear electrically when I type the closing
>>>> ")". Note that balanced_parens could in turn nested use of "!()", as
>>>> in A!(B!(C)), and they should all be paired using chevrons. The
>>>> underlying file should not contain the chevrons, just the ASCII
>>>> representation using "!(" and ")".
>>>>
>>>> I haven't done much elisp programming beyond the common .emacs
>>>> configuration tricks, so I don't know where to start. A few searches
>>>> suggested that overlays may be what I'm looking for... any ideas and
>>>> pointers? Thank you.
>>> If you didn't ask for recursion, this could have be done with
>>> font-locking.
>>> (font-lock-add-keywords nil
>>>   '(("\\(!(\\)[^()]*\\()\\)"      0 (progn
>>>          (compose-region (match-beginning 1) (match-end 1) ?« 'decompose-region)
>>>          (compose-region (match-beginning 2) (match-end 2) ?» 'decompose-region)
>>>          nil))))
>>> But since this uses regular expressions, it won't work for recursive
>>> !(...).
>>> You can still use compose-region, but you'll have to implement the
>>> parsing yourself.  Perhaps this could be hooked on the code doing the
>>> parenthesis balancing?
>> I think I'd be happy with a nonrecursive region to get my feet
>> wet. How do I use your font-lock-add-keywords code? I added it to both
>> my .emacs and my d-mode.el file, to no avail.
> 
> You could run it from a d-mode-hook if it exists, ensuring that
> font-lock-mode is enabled.
> 
> (add-hook 'd-mode-hook 
>           (lambda () 
>             (font-lock-add-keywords nil
>               '(("\\(!(\\)[^()]*\\()\\)"      0 (progn
>                      (compose-region (match-beginning 1) (match-end 1) ?« 'decompose-region)
>                      (compose-region (match-beginning 2) (match-end 2) ?» 'decompose-region)
>                      nil))))
>             (font-lock-mode 1)))
> 

Thanks! I got that working. It ought to get me started.

Regards,

Andrei