Hi Perlmonks,

Is if possible to have a string interpreted as a literal without pre-escapting in a regex. Consider: 

#!/opt/local/bin/perl
my $a = "Tick F***ing Tock";
my $b = "Friday night at 11:30pm the start of a new series, 'Tick F***
+ing Tock' explores...";

if ($b =~ /$a/)
{
  print "..do something..\n";
}

[download]
This will return: 
$ ./t.pl
Nested quantifiers in regex; marked by <-- HERE in m/Tick F** <-- HERE
+ *ing Tock/ at ./t.pl line 5.

[download]
Of course this will work: 
#!/opt/local/bin/perl
my $a = "Tick F***ing Tock";
my $b = "Friday night at 11:30pm the start of a new series, 'Tick F***
+ing Tock' explores...";

$a =~ s/([\(\)\[\]\{\}\\\*\?\.\$\^\@\!\&])/\\$1/g;

if ($b =~ /$a/)
{
  print "..do something..\n";
}

[download]
Result: 
$ ./t.pl
..do something..

[download]
However there will result in a long list of escapes to make parsing safe as '$a' in my script is dynamic and not fixed like in this example... Also there will no doubt be a significant performance hit considering the number of times I'd be looping over the regex...

Thanks in advance.

In reply to Switch/Format to not interpret metacharacters in regex? by mis

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