The operator you speak of is not the range operator, but is in fact the flip-flop operator (oooh, it's a sneaky one!). I believe this was grabbed from AWK, and is *uber* handy when doing text processing (like AWK). You can have all sorts of funky variations on the above, from fancy regexps to simple line numbers. I shall use the example from the always informative perl docs (man perlop) -

if (101 .. 200) { print; }  # print 2nd hundred lines
next line if (1 .. /^$/);   # skip header lines
s/^/> / if (/^$/ .. eof()); # quote body

# parse mail messages
while (<>) {
    $in_header =   1  .. /^$/;
    $in_body   = /^$/ .. eof();
    # do something based on those
    } continue {
        close ARGV if eof;              # reset $. each file
}
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Indeed a thing of beauty!
HTH

broquaint