regex search fails

[stephanm]

Hi Monks, I have a little program file that's meant to search itself for lines which contain a specific word which is the first word in line 3 (ie $testVar). For some reason it does not work. Anyone clues as to how to make this work?

### this file is called regex.pl
my $testVar;
$testVar = "January";

### read this file
open(FH,"<regex.pl") or die "cannot open file";
my @myself = <FH>;
close(FH);
 
### make $pattern: $testVar
$myself[2]=~/([^ ]+)/;
my $pattern = $1;
print "Pattern: $pattern\n";

### print lines with this pattern
for(@myself)
{
  print if /$pattern/;
}

Thanks.

[jethro]

Change the line in the loop to

    print if /\Q$pattern\E/;

This is equivalent to $pattern= quotemeata($pattern); before the loop. The '$' in your pattern is interpreted as special char in your regex, thats why it isn't working

[ikegami]

If the "solution" is

print if /\Q$pattern\E/;

then $pattern doesn't contains a regexp pattern as its name implies. The variable should be renamed

my $search_str = $1;
...
print if /\Q$search_str/;

or quotemeta should be called earlier.

my $pattern = quotemeta($1);  # aka "\Q$1"
...
print if /$pattern/;

[friedo]

Try print if /\Q$pattern/. Since your pattern contains the literal string '$testVar', using the \Q escape will prevent it from being interpolated in the match.

[stephanm]

Thanks everyone. The \Q did the trick.