One of the reasons O'Reilly books can't charme is are the poor indices . . .

Perhap. I'm comparing the Camel's index with the multitude of "Learning Perl for Fools" books out there, where they basically slap an index with a few common terms and leave the rest to the poor sod that bought the book.

What I also don't understand is that you wouldn't buy certain classes of books, because they are easily outdated, yet you break a lance for the Camel.

How much fundamental of the Camel was really obsoleted by 5.6.* or 5.8.*? Declaring variables is still the same. Looping and conditionals are the same. Declaring subroutines is the same, with at best a few attributes being added, if anything. Builtins are pretty much the same, with a few details being different. Complex datastructures, packages/modules, and OO programming are the same (notwithstanding meryln's complaints about ref $class || $class;, or the various other object systems you can use under Perl). Trying to output native, optimized code from your Perl code is still a tricky proposition. Tied filehandles became useable in 5.6.0 (IIRC), but that's a fairly small portion of the book, and it covers them anyway. Threading became somewhat useable in 5.8.0, but again, it's a small part of the book.

So small, specific sections might be a bit out of date, but I don't forsee it being unuseable at least until Perl6. That's a long ways off and a lot of Perl5 stuff will still be applicable by then. Probably Perl4, too.

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated