Re^2: OO Design Question with Hashes of Arrays

Thanks for the input everyone. I do understand (somewhat) hashes of arrays data structure.

I have looked into moose and others as suggested. My needs are so small at this point (I'm almost done) that I think I'm going to keep hacking away at the base perl system.

Anonymous Monk, thank you so much. This was just what I needed and it works exactly as you demonstrated. I am ignorant of some of the syntax that you used and I was wondering if you could point me to an article that explains the syntax usage? I googled and could not find anyone using the syntax quite this way in my searches.

Specifically...

= $_ for @_;

I'm guessing this is shorthand for a for loop, but, again, my searches have been fruitless and the man pages have not been helpful.

Thank you again monks for the assistance!

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Re^3: OO Design Question with Hashes of Arrays by AnomalousMonk (Archbishop) on Jun 26, 2013 at 17:09 UTC
... an article that explains the syntax usage ... `= $_ for @_;` I'm guessing this is shorthand for a for loop ... This is the statement modifier form of a `for`-loop. It iterates over the elements of a `LIST` and 'topicalizes' (or aliases with localization) the default scalar `$_` (see perlvar) to each element in turn. Because `$_` is aliased, elements of an array can be altered "in place", which can be very helpful, even essential, in dealing with large arrays. `>perl -wMstrict -le "$_ = 'same as it ever was'; ;; my @ra = (1, 2, 3, 4); ;; $_ = $_ + 990 for @ra; print qq{@ra}; ;; print 880 + $_ for 1, 2, 3, 4; ;; print $_; " 991 992 993 994 881 882 883 884 same as it ever was` [download] (For some insight into the difference between a list and an array, try executing the statement `$_ = $_ + 990 for 1, 2, 3, 4;` instead.)	[reply] [d/l] [select]

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Re^3: OO Design Question with Hashes of Arrays
by AnomalousMonk (Archbishop) on Jun 26, 2013 at 17:09 UTC

... an article that explains the syntax usage ...
= $_ for @_;
I'm guessing this is shorthand for a for loop ...

This is the statement modifier form of a for-loop. It iterates over the elements of a LIST and 'topicalizes' (or aliases with localization) the default scalar $_ (see perlvar) to each element in turn. Because $_ is aliased, elements of an array can be altered "in place", which can be very helpful, even essential, in dealing with large arrays.

>perl -wMstrict -le
"$_ = 'same as it ever was';
 ;;
 my @ra = (1, 2, 3, 4);
 ;;
 $_ = $_ + 990 for @ra;
 print qq{@ra};
 ;;
 print 880 + $_ for 1, 2, 3, 4;
 ;;
 print $_;
"
991 992 993 994
881
882
883
884
same as it ever was
[download]

(For some insight into the difference between a list and an array, try executing the statement
$_ = $_ + 990 for 1, 2, 3, 4;
instead.)

[reply]
[d/l]
[select]