variable declaration, was RE: moving to the next line

From: Chris Devers (cdevers_at_pobox.com)
Date: 12/17/04 

Date: Fri, 17 Dec 2004 09:17:05 -0500 (EST)
To: "Charles K. Clarkson" <cclarkson@htcomp.net>

On Thu, 16 Dec 2004, Charles K. Clarkson wrote:

> Don't declare all your variables at the beginning
> of the script. It works in other languages, but not
> in perl. Declare them as you go.

Out of curiosity, why this rule?

When taking programming classes in college, it was drummed into us that
having a data dictionary at the top of a scope was a good habit, and
it's something that I've generally done with the Perl I've written.

Several people on this list have discouraged the habit. How come?

I can see the logic in discouraging global variables, but predeclaring
variables at the top of a scope -- the beginning of a subroutines, and a
small handful in the main block -- still seems acceptable to me. Indeed,
waiting to declare until the variable is used is, to my thinking, kind
of defeating the point of using 'strict': if the declarations are
scattered all over the place, why bother being strict?

Perl is an eccentric language to be sure, but why over this? Anyone care
to explain?

Thanks :-) 

-- 
Chris Devers

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