I have no idea where to start parsing

You may not know it, but it's very easy to tap into perl's own parser, and find out what it thinks of a given piece of code:

% perl -MO=Deparse chester
chester syntax OK
$+ + s/\\\s q\\+//s
    + s/$/$$/s / s///s
    . s[{q`!^/s.`^q\s][. s]s
    . s/\d*/do { 'JAPH' }/es + 'es)/$'
    + s/$_\$/$_$_/s
    + s///s
    + print($_);

[download]

(whitespace added for clarity).

Once it's been through the wringer it becomes clear what is happening (well, to me at least). As it turns out, it looked like chester threw a couple of diversions in the mix.

It used to be that a particularly clever obfu will cause B::Deparse to crash, which would prevent such casual analysis. As a result, for better or worse, B::Deparse has lots more smarts these days and it's just about impossible to trip it up. Much kudos is earnt by managing to do so.

• another intruder with the mooring in the heart of the Perl

In reply to Re^2: Line noise (use B::Deparse) by grinder
in thread Line noise by chester

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.