Visitor here is a gedit user; how to interest him in Emacs?

Visitor here is a gedit user; how to interest him in Emacs?

[David Combs]

Recently, I've been trying to interest someone in
this most wonderful program, (gnu) Emacs.

Trouble is, he's already using Gedit (google's editor);

every time I try to show him some Emacs concep, he says
that he can do that in gedit also.

This guy is really, really smart, so much though that
I myself would think that he could really benefit
himself by learning it.

Now, usually we're separated by 1,000 miles, communicating
by phone, which which it is almost impossible to demonstrate
a program: "Now hit control-X then Control-f, and then 
move the cursor over to ...." -- not at all simple.

Anyway, he's here for another 30 or so hours -- so what
can I show him that might excite him into further
investigation?

Any ideas will be most welcome!


Thanks,

David

Re: Visitor here is a gedit user; how to interest him in Emacs?

[Elena]

Can Gedit talk to external processes, both ways? Does it have
something like Eshell? Unlike Bash,  Eshell will be with you wherever
Emacs is.

Check `wdired-change-to-wdired-mode'.

Check http://www.emacswiki.org/emacs/grep-edit.el

Check the --script option, which allows you to use Emacs Lisp for
batch text processing.

Check `C-h' and show him how explorable Emacs is.

However, if that guy just needs an editor, just tell him to stick with
Gedit.

Re: Visitor here is a gedit user; how to interest him in Emacs?

[Marc Mientki]

Am 05.08.2010 08:12, schrieb David Combs:

> every time I try to show him some Emacs concep, he says
> that he can do that in gedit also.

Then let it do the following. C code is given with matrix declaration as:
   int matrix[3][3];

but someone has used the 1-based indexing instead of C 0-based:

   matrix[1][1] = 2;
   matrix[1][2] = 6;
   matrix[1][3] = 1;
   matrix[2][1] = 9;
   matrix[2][2] = 5;
   matrix[2][2] = 12;
   matrix[3][1] = 11;
   matrix[3][2] = 0;
   matrix[3][2] = 7;


It is simply a bug so the task is to convert this to:

   matrix[0][0] = 2;
   matrix[0][1] = 6;
   matrix[0][2] = 1;
   matrix[1][0] = 9;
   matrix[1][1] = 5;
   matrix[1][1] = 12;
   matrix[2][0] = 11;
   matrix[2][1] = 0;
   matrix[2][1] = 7;

In general, there may be hundreds or thousands of references to matrix,
so the solution must be intelligent enough that such things are not
taken into account:

   Amatrix[1][2]
   InMatrix[2][1]
   _matrix[2][2]
   matrix[2][1][2]
   a_matrix[3][1]
   .matrix[3][2]

But this very well:
   +matrix[1][3]
   - matrix[3][2]


Can Gedit process such thing?

regards
Marc

Re: Visitor here is a gedit user; how to interest him in Emacs?

[David Combs]

In article <i3dqfp$tmq$1@news.onet.pl>,
Marc Mientki  <mientki@nonet.com> wrote:
>Am 05.08.2010 08:12, schrieb David Combs:
>
>> every time I try to show him some Emacs concep, he says
>> that he can do that in gedit also.
>
>Then let it do the following. C code is given with matrix declaration as:
>   int matrix[3][3];
>
>but someone has used the 1-based indexing instead of C 0-based:
>
>   matrix[1][1] = 2;
>   matrix[1][2] = 6;
>   matrix[1][3] = 1;
>   matrix[2][1] = 9;
>   matrix[2][2] = 5;
>   matrix[2][2] = 12;
>   matrix[3][1] = 11;
>   matrix[3][2] = 0;
...
...
...


OK -- now, to show him the POWER of emacs, PLEASE, PLEASE
show the solution to the problem, ie via keyboard macros,
functions, commands, etc.


And I bet we'll ALL learn some nice technique from
your implementation.


THANKS!

David

Re: Visitor here is a gedit user; how to interest him in Emacs?

[David Kastrup]

dkcombs@panix.com (David Combs) writes:

> In article <i3dqfp$tmq$1@news.onet.pl>,
> Marc Mientki  <mientki@nonet.com> wrote:
>>Am 05.08.2010 08:12, schrieb David Combs:
>>
>>> every time I try to show him some Emacs concep, he says
>>> that he can do that in gedit also.
>>
>>Then let it do the following. C code is given with matrix declaration as:
>>   int matrix[3][3];
>>
>>but someone has used the 1-based indexing instead of C 0-based:
>>
>>   matrix[1][1] = 2;
>>   matrix[1][2] = 6;
>>   matrix[1][3] = 1;
>>   matrix[2][1] = 9;
>>   matrix[2][2] = 5;
>>   matrix[2][2] = 12;
>>   matrix[3][1] = 11;
>>   matrix[3][2] = 0;
> ...
> ...
>
> OK -- now, to show him the POWER of emacs, PLEASE, PLEASE
> show the solution to the problem, ie via keyboard macros,
> functions, commands, etc.

Hm?  That's not particularly hard.

C-M-% \<matrix\[\([0-9]+\)]\[\([0-9]+\)] RET
matrix[\,(1- \#1)][\,(1- \#2)] RET

> And I bet we'll ALL learn some nice technique from
> your implementation.

I doubt it.  That's more basic than the more complex examples in the
Emacs manual for regexp replacement.

-- 
David Kastrup

Re: Visitor here is a gedit user; how to interest him in Emacs?

[Marc Mientki]

Am 05.08.2010 08:12, schrieb David Combs:

> every time I try to show him some Emacs concep, he says
> that he can do that in gedit also.

Another example. Let him convert that

   value_at_1_4 = 10;
   value_at_2_2 = 11;
   value_at_5_1 = 300;

to this:

   value[3][0] = 10;
   value[1][1] = 11;
   value[0][4] = 300;

So he should extract two last number parts from variable name, remove 
'_at_' from name, use both index for c-array-indexing but in reverse 
order and 0-based (original was 1-based). Of course everything in one 
pass in full automatic :-)

regards
Marc

Re: Visitor here is a gedit user; how to interest him in Emacs?

[Pascal J. Bourguignon]

Marc Mientki <mientki@nonet.com> writes:

> Am 05.08.2010 08:12, schrieb David Combs:
>
>> every time I try to show him some Emacs concep, he says
>> that he can do that in gedit also.
>
> Another example. Let him convert that
>
>   value_at_1_4 = 10;
>   value_at_2_2 = 11;
>   value_at_5_1 = 300;
>
> to this:
>
>   value[3][0] = 10;
>   value[1][1] = 11;
>   value[0][4] = 300;

> So he should extract two last number parts from variable name, remove
> _at_' from name, use both index for c-array-indexing but in reverse
> order and 0-based (original was 1-based). Of course everything in one
> pass in full automatic :-)

Even better:

/*

matrix is:
    | 2  9 11 | 
    | 6  5  0 |
    | 1 12  7 |
    
*/

and have it transform this comment into the matrix intialization code:

matrix[1][1]=2;
matrix[1][2]=6;
matrix[1][3]=1;
matrix[2][1]=9;
matrix[2][2]=5;
matrix[2][3]=12;
matrix[3][1]=11;
matrix[3][2]=0;
matrix[3][3]=7;






(defun matrix-to-c (start end)
   (interactive "r")
   (goto-char start)
   (when (re-search-forward "\\([_A-Za-z][_A-Za-z0-9]*\\)  *is *:" end t)
     (let ((name (match-string 1))
           (data '()))
       (while (re-search-forward "|\\(.*\\)|" end t)
           (push (first (read-from-string (concat "(" (match-string 1) ")"))) data))
       (setf data (reverse data))
       (search-forward "*/")
       (goto-char (match-end 0))
       (insert "\n")
       (loop
          for j from 1 to (length data)
          do (loop
                for i from 1 to (length (first data))
                do (insert (format "%s[%s][%s]=%s;\n" name j i (elt (elt data (1- i)) (1- j)))))))))

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

Re: Visitor here is a gedit user; how to interest him in Emacs?

[Marc Mientki]

Am 05.08.2010 14:57, schrieb Pascal J. Bourguignon:
> Marc Mientki<mientki@nonet.com>  writes:
>
>> Am 05.08.2010 08:12, schrieb David Combs:
>>
>>> every time I try to show him some Emacs concep, he says
>>> that he can do that in gedit also.
>>
>> Another example. Let him convert that
>>
>>    value_at_1_4 = 10;
>>    value_at_2_2 = 11;
>>    value_at_5_1 = 300;
>>
>> to this:
>>
>>    value[3][0] = 10;
>>    value[1][1] = 11;
>>    value[0][4] = 300;
>
>> So he should extract two last number parts from variable name, remove
>> _at_' from name, use both index for c-array-indexing but in reverse
>> order and 0-based (original was 1-based). Of course everything in one
>> pass in full automatic :-)
>
> Even better:
>
> /*
>
> matrix is:
>      | 2  9 11 |
>      | 6  5  0 |
>      | 1 12  7 |
>
> */
>
> and have it transform this comment into the matrix intialization code:
>
> matrix[1][1]=2;
> matrix[1][2]=6;
> matrix[1][3]=1;
> matrix[2][1]=9;
> matrix[2][2]=5;
> matrix[2][3]=12;
> matrix[3][1]=11;
> matrix[3][2]=0;
> matrix[3][3]=7;
>
>
>
>
>
>
> (defun matrix-to-c (start end)
>     (interactive "r")
>     (goto-char start)
>     (when (re-search-forward "\\([_A-Za-z][_A-Za-z0-9]*\\)  *is *:" end t)
>       (let ((name (match-string 1))
>             (data '()))
>         (while (re-search-forward "|\\(.*\\)|" end t)
>             (push (first (read-from-string (concat "(" (match-string 1) ")"))) data))
>         (setf data (reverse data))
>         (search-forward "*/")
>         (goto-char (match-end 0))
>         (insert "\n")
>         (loop
>            for j from 1 to (length data)
>            do (loop
>                  for i from 1 to (length (first data))
>                  do (insert (format "%s[%s][%s]=%s;\n" name j i (elt (elt data (1- i)) (1- j)))))))))
>

Very fine example!

Normaly I prefere to write small piece elisp code to solve such task,
too. But sometimes I find a puzzle with macros very funny, especialy in
non trivial cases like this one. So I wrote matrix-to-c as macro. With
some limitations it works fine.

First limitation: I expect matrix form without '|':

       2  9 11
       6  5  0
       1 12  7

Second: I use genial macro-math.el from Nikolaj Schumacher with
following key bindings:

(global-set-key "\C-x~" 'macro-math-eval-and-round-region)
(global-set-key "\C-x=" 'macro-math-eval-region)


This is my solution:

M-C-s                   ;; isearch-forward-regexp
[0-9]                   ;; self-insert-command * 5
RET                     ;; newline-and-indent
C-a                     ;; move-beginning-of-line
TAB                     ;; c-indent-line-or-region
C-M-SPC                 ;; mark-sexp
C-x r s                 ;; copy-to-register
1                       ;; self-insert-command
C-w                     ;; kill-region
matrix[                 ;; self-insert-command * 7
C-SPC                   ;; set-mark-command
(                       ;; c-electric-paren
C-x C-k <tab>
-1                      ;; self-insert-command * 2
)                       ;; c-electric-paren
/                       ;; c-electric-slash
3                       ;; self-insert-command
C-u 0 C-x ~             ;; macro-math-eval-and-round-region
][                      ;; self-insert-command * 2
C-SPC                   ;; set-mark-command
C-u C-x C-k <tab>
%3                      ;; self-insert-command * 2
C-x =                   ;; macro-math-eval-region
]                       ;; self-insert-command
SPC                     ;; self-insert-command
=                       ;; self-insert-command
SPC                     ;; self-insert-command
C-u C-x r i             ;; insert-register
1                       ;; self-insert-command
;                       ;; c-electric-semi&comma
RET                     ;; newline-and-indent


Or ready to use:

(fset 'matrix-to-c
    [?\C-\M-s ?\[ ?0 ?- ?9 ?\] ?\C-m ?\C-a ?\C-i ?\C-\M-  ?\C-x ?r ?s ?1 
?\C-w ?m ?a ?t ?r ?i ?x ?\[ ?\C-  ?\( ?\C-x ?\C-k tab ?- ?1 ?\) ?/ ?3 
?\C-u ?0 ?\C-x ?~ ?\] ?\[ ?\C-  ?\C-u ?\C-x ?\C-k tab ?% ?3 ?\C-x ?= ?\] 
?  ?= ?  ?\C-u ?\C-x ?r ?i ?1 ?\; ?\C-m])

So now one can paste matrix form into C code:

       2  9 11
       6  5  0
       1 12  7

init emacs macro counter to 0 (C-x C-k C-c 0 RET) and then call 9 times
matrix-to-c:

C-u 9 M-x matrix-to-c

and we get:

   matrix[0][0] = 2;
   matrix[0][1] = 9;
   matrix[0][2] = 11;

   matrix[1][0] = 6;
   matrix[1][1] = 5;
   matrix[1][2] = 0;

   matrix[2][0] = 1;
   matrix[2][1] = 12;
   matrix[2][2] = 7;

(I used first index as row, second as col, 0-based).

I love Emacs! :-)


regards
Marc

Re: Visitor here is a gedit user; how to interest him in Emacs?

[Elena]

Check orgtbl-mode, too. I think there is a screencast here (I can't
watch Youtube videos right now):

http://www.google.it/url?url=http://www.youtube.com/watch%3Fv%3DEQAd41VAXWo&rct=j&sa=X&ei=0HNaTIy2I5egsQbpoYl5&ved=0CBkQuAIwAA&q=emacs+power+can+your+editor+do+this&usg=AFQjCNH2JLR5CFXOs_OXnJQUvn5sI3UzMQ&cad=rja

Re: Visitor here is a gedit user; how to interest him in Emacs?

[despen]

dkcombs@panix.com (David Combs) writes:

> Recently, I've been trying to interest someone in
> this most wonderful program, (gnu) Emacs.
>
> Trouble is, he's already using Gedit (google's editor);

Gnome Edit.  It's only hosted at google code.

> every time I try to show him some Emacs concep, he says
> that he can do that in gedit also.

Leave him alone.  You'll only annoy him.

Gedit focuses on simplicity.  Some users like that over
being able to do almost anything.

Re: Visitor here is a gedit user; how to interest him in Emacs?

[TheFlyingDutchman]

> Recently, I've been trying to interest someone in
> this most wonderful program, (gnu) Emacs.
>
> Trouble is, he's already using Gedit (google's editor);

What is he using Gedit for?


Don't know if he is a C/C++ programmer, but it is nice to be able to
compile - get the compiler output and then jump to the error in the
source code. From looking at Gedit it doesn't look that it can do that
IDE-type function.