regex search and replace issue

[Anonymous Monk]

if (lc($Message) =~ /^db /) {
print "Content-type:text/html\n\n";
print "c=$Message<br>\n";
  $Message = s/^db //;
  $Message = s/^Db //;
  $Message = s/^dB //;
  $Message = s/^DB //;
print "m=$Message";
exit;
}

gives result:

c=Db test4<br>
m=

I'm expecting the Db(space) to be removed but the whole expression is being taken out!

[Anonymous Monk]

Assignment operator = is not the same as binding operator =~

If you want to make matches, or substitutions, on $variable, you need to use binding operator

[jonnyfolk]

oh, I'm as careless as careless can be. Thanks to all for pointing it out and helpful suggestions

[toolic]

Perl can help prevent you from being careless... if you use strict and warnings. You would have gotten a warning message which would have pointed you to the offending lines.

[MVS]

Anonymous Monk has the right solution, but just wanted to add that you can simplify your regexes using character classes. You can replace all four with:

$Message =~ s/^[Dd][Bb] //;

[Utilitarian]

Or by using the case insensitivity modifier to the regex.

$Message =~ s/^db //i;

[mrstlee]

Just to flesh out Utilitarian's answer:

    if ($Message =~ /^db /i) { 
        print "Content-type:text/html\n\n"; 
        print "c=$Message<br>\n";
         $Message =~ s/^db //i; 
        print "[m=$Message]\n"; 
        exit; 
    }

[hbm]

Or, since you're exiting and therefore don't need the modified $Message further down, just capture any trailing stuff and print once:

if ($Message =~ /db (.*)/i){
   print "Content-type:text/html\n\n",
         "c=$Message<br>\n",
         "[m=$1]\n";
   exit;
}