c:\@Work\Perl\monks>perl -wMstrict -le
"my $s = qq{foo fee fie\nbar bell\nbaz biz boz};
 print qq{[[$s]]};
 print '--------';
 ;;
 my ($x) = $s =~ m{ ^ foo (.+) }x;
 my ($y) = $s =~ m{ ^ bar (.+) }x;
 my ($z) = $s =~ m{ ^ baz (.+) }x;
 print qq{'$x'  '$y'  '$z'};
 print '--------';
 ;;
 ($x) = $s =~ m{ ^ foo (.+) }xm;
 ($y) = $s =~ m{ ^ bar (.+) }xm;
 ($z) = $s =~ m{ ^ baz (.+) }xm;
 print qq{'$x'  '$y'  '$z'};
"
[[foo fee fie
bar bell
baz biz boz]]
--------
Use of uninitialized value $y in concatenation (.) or string at -e line 1.
Use of uninitialized value $z in concatenation (.) or string at -e line 1.
' fee fie'  ''  ''
--------
' fee fie'  ' bell'  ' biz boz'