topic Re: Regular expression query !!should be a good one in Operating System - HP-UX

Regular expression query !!should be a good one

Deepak_5 — Fri, 06 Jul 2001 09:47:32 GMT

Hi,

I have a definition in my file

int func(/* sdsd*/int a, /*deep*/char b);

I need to change it to
int func( int a, char b);
or
int func(int a,char b);

Basically, I need to get rid of the comments in the line.

Is there a regular expression substitution for this.
Also Note in "vi" I tried:
:%s/\/\*.*\*\///g

I tired may other patterns with "(" and ")" stuff, but somehow did not work.

Got any idea, please let me know.

Thanks and Regards
Deepak

Re: Regular expression query !!should be a good one

Volker Borowski — Fri, 06 Jul 2001 09:59:16 GMT

Deepaq,

you just provided one DOT. So only any comment consisting of a single char will be replaced.

I am not so deep in regexps, but I would try

%s/\/\*.\*\///g
%s/\/\*..\*\///g
%s/\/\*...\*\///g
and so on (yes, not very sophisticated)...

Volker

Re: Regular expression query !!should be a good one

Robin Wakefield — Fri, 06 Jul 2001 10:12:20 GMT

%s/\/\*[^\*]*\*\///g

should do it.

Robin

Re: Regular expression query !!should be a good one

Thierry Poels_1 — Fri, 06 Jul 2001 10:34:44 GMT

Hi,

:%s;/\*[^\*]*\*/;;g
or
:%g;func;s;/\*[^\*]*\*/;;g (for only the lines containing "func")

should work too; by replacing the seperator by ";" you don't need to escape the "/" in your search.

BTW: s;/\*.*\*/;... will replace everyting between the first "/*" and the last "*/" on a line !!

regards,
Thierry.

Re: Regular expression query !!should be a good one

Deepak_5 — Fri, 06 Jul 2001 12:00:00 GMT

Hi ,

The seems to be some problem, my commets cannot have '*' or '/'
e.g.
int func1( /* *sdf */ int *a ,/* */int b);
This is a valid C statement.

Can Anyone handle this as well ?

Thanks and Regards
Deepak

Re: Regular expression query !!should be a good one

Thierry Poels_1 — Fri, 06 Jul 2001 12:24:07 GMT

hmmz,
:%s;/\*[^/]*\*/;;g
will allow "*" in your comments, but no "/" :)
So if you run both substitutes, everything should be OK.

:%s;/\*[a-bA-Z0-9*/.:\; ]*\*/;;g
will do the trick in one step, add any character you need between the square brackets.

good luck,
Thierry.

Re: Regular expression query !!should be a good one

Deepak_5 — Fri, 06 Jul 2001 13:00:17 GMT

Thanks Theiry,but
:%s;/\*[a-bA-Z0-9*/.:\; ]*\*/;;g

did not work fine for me .
e.g. int func1( /* sdf / *ddd */ int *a ,int b);
is the input.

There has to be way..

Thanks and Regards
Deepak

Re: Regular expression query !!should be a good one

Rodney Hills — Fri, 06 Jul 2001 13:32:18 GMT

Most regular expressions are greedy (matching as much as possible). Perl5 has an option to a reg expr to match a minimum. So try the following-

perl -p -i -e 's{/\*.*?\*/}{}' yourprog.c

The .*? will only match until the FIRST */ is found.

Re: Regular expression query !!should be a good one

David Totsch — Fri, 06 Jul 2001 17:38:10 GMT

Deepak:

try this with sed(1):

/func/ s#$^.*$$\/\*..*\*\/$$.*$$\/\*..*\*\/$$.*$$#\1 \3 \5#g

$^.*$ starts matching the front
of input lines
$\/\*..*\*\/$ matches the comment you
want to discard (at least
one character e.g. "/* */")
$.*$ captures the text between
comments
$\/\*..*\*\/$ matches the second comment
WARNING: _requires_ second cmnt
$.*$$ captures text up to the end
of the line

\1 \3 \5 recalls what was matched by
those parenthetical statements
numbered starting with 1 from
left to right

Again, this statement will "hit" only on lines
that have two embedded comments.

Enjoy,
-dlt-

Re: Regular expression query !!should be a good one

someone_4 — Fri, 06 Jul 2001 20:30:40 GMT

If anyone is still reading this post.
Can someone tell me what you are talking about?

thanks

Richard

Re: Regular expression query !!should be a good one

Deepak_5 — Sat, 07 Jul 2001 05:08:42 GMT

Richard,

We still are very much there to get a perfect solution.

The input is this line
int func1( /* sdf * */ int *a ,/* / */ int b/* wewe */);

Reduce it to.
int func1( int *a ,int b);

Note:
The may be any number of comments in a line , and any valid
character in those comments.

Thanks for the all the responses.
With response, we have got till now, there seems
to be no way through pure regular expression,
except for the perl stuff(Cannot use perl though).
Can be awk/sed.

Thanks and Regards
Deepak