#### Program:
# The Regular Shrink Program
print "shrink: Hello.\n";
for (;;) {
    print "  mark: ";
    $gibberish = <STDIN>;
    chomp($gibberish);
    if    ( $gibberish =~ /Good.*bye|^Bye/ ) { last; }
    print "\ndoctor: Did you say: \"$gibberish\"\n";
}
print "\ndoctor: Goodbye, sucker.";
__END__

#### Output:
doctor: Hello.
  mark: Hi. How are you?
  
doctor: Did you say: "Hi. How are you?"?
  mark: Yes. 

doctor: Did you say: "Yes"?
  mark: You are crazy! Good  bye!
  
doctor: Goodbye, sucker.
    
        
#### Notes on Code Fragments:

$gibberish =~ /.../      # is true if the variable $gibberish matches
                         # the pattern ...
    /...|.../            # the | means or
                         # the pattern is matched if either ... is matched
    .                    # any character (well. almost any character)
    .*                   # zero or more of .
    ^                    # matches the start of the string    

############################# that's all folks #################################