$1, $2, $3, .... 
Si no hubiera emparejamiento se retorna la lista vacía.
Si lo hubiera pero no hubieran paréntesis se retorna la lista 
(1).
   1 #!/usr/bin/perl -w
   2 $foo = "one two three four five";
   3 ($F1, $F2, $Etc) = ($foo =~ /^\s*(\S+)\s+(\S+)\s*(.*)/);
   4 print "List Context: F1 = $F1, F2 = $F2, Etc = $Etc\n";
   5 # This is equivalent to:
   6 ($F1, $F2, $Etc) = split(' ',$foo,3);
   7 print "Split: F1 = $F1, F2 = $F2, Etc = $Etc\n";
Observa el resultado de la ejecución:
> escapes.pl List Context: F1 = one, F2 = two, Etc = three four five Split: F1 = one, F2 = two, Etc = three four five
Casiano Rodríguez León
