I was able to come up with a working version with a much simpler regex. The regex matches just the if statement, then removes the next set of curly braces. One caveat though - it only removes braces for the first if statement. Subsequent ones would not be effected.
One thing you might keep in mind is that it's often a good idea to backslash '\' characters like braces if your using them in a non-grouping way in your regex. I tend to backslash all non-alphanumeric chars in my regexes, just to be safe. 
#/usr/bin/perl -w
use strict;
my $data;
while(<DATA>) {
 last if ($_ eq "");
 $data .= $_;
}

print $data;
if ( $data =~ /if.*?\{/s ) { # New RegEx
 $data =~ s/\{//;
 $data =~ s/\}//;
}

print $data;
__DATA__
if (c=e)
     {    //delete these curly braces               
      call pgme;
      call pgmd;
      }                //delete these curly braces
     else
       {call pgmd;     // keep these curly braces
        call pgmc;}

[download]
Output:
if (c=e)
                //delete these curly braces                   
      call pgme;
      call pgmd;
                      //delete these curly braces
     else
       {call pgmd;     // keep these curly braces
        call pgmc;}

[download]

Rich36
There's more than one way to screw it up...

In reply to Re: pattern matching by Rich36
in thread pattern matching by sliles

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