use strict;
use warnings;

print "Gimme a string: ";
my $str = <STDIN>;
chomp $str;
print "Gimme a RegEx: ";
my $pattern = <STDIN>;
chomp $pattern;

my $rex;
{ # a block to localize $@
 local $@;
 # eval the regex 
 eval{ $rex = qr/$pattern/ };
 # die if errors
 die "error compiling regex!" if $@;

} # end of the localizing block


print $str =~ /$rex/ ? "Yes!" : "No.";