A loop

Here is a script named lextest.t copied from the perlop(1) man page and compacted to hide the structure:

$_= <<'EOL';
   $url = new URI::URL "http://www/";   die if $url eq "xXx";
EOL
LOOP:{print(" digits"),redo LOOP if/\G\d+\b[,.;]?\s*/gc;print(" lowercase"),
redo LOOP if/\G[a-z]+\b[,.;]?\s*/gc;print(" UPPERCASE"),redo LOOP 
if/\G[A-Z]+\b[,.;]?\s*/gc;print(" Capitalized"),
redo LOOP if/\G[A-Z][a-z]+\b[,.;]?\s*/gc;
print(" MiXeD"),redo LOOP if/\G[A-Za-z]+\b[,.;]?\s*/gc;print(
" alphanumeric"),redo LOOP if/\G[A-Za-z0-9]+\b[,.;]?\s*/gc;print(" line-noise"
),redo LOOP if/\G[^A-Za-z0-9]+/gc;print". That's all!\n";}

The command perltidy lextest.t produces a file named lextest.t.tdy with this result:

$_ = <<'EOL';
   $url = new URI::URL "http://www/";   die if $url eq "xXx";
EOL
LOOP: {
    print(" digits"),       redo LOOP if /\G\d+\b[,.;]?\s*/gc;
    print(" lowercase"),    redo LOOP if /\G[a-z]+\b[,.;]?\s*/gc;
    print(" UPPERCASE"),    redo LOOP if /\G[A-Z]+\b[,.;]?\s*/gc;
    print(" Capitalized"),  redo LOOP if /\G[A-Z][a-z]+\b[,.;]?\s*/gc;
    print(" MiXeD"),        redo LOOP if /\G[A-Za-z]+\b[,.;]?\s*/gc;
    print(" alphanumeric"), redo LOOP if /\G[A-Za-z0-9]+\b[,.;]?\s*/gc;
    print(" line-noise"),   redo LOOP if /\G[^A-Za-z0-9]+/gc;
    print ". That's all!\n";
}

Notice how perltidy has done some nice vertical alignment here.