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RE: Debugging and 'uninitialized value in concatenation' question

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From:
Jason Frisvold
Date:
April 26, 2002 12:09
Subject:
RE: Debugging and 'uninitialized value in concatenation' question
Message ID:
AFC704CE41DA93429C9411A6DD93F07501770CCB@EXCHANGE5.corp.ptd.net
Hrm..  I'll run some tests with it and see what I find out...  Sounds
promising if it really is a preprocessor...  So does it just do
something along the lines of a cat <file> | grep -v <stuff> and then
execute the output?  (I realize that is simplifying it by a great deal)

I'm just trying to wrap my head around this...  The program (actually
programs) that I've been writing runs anywhere from once every 5 minutes
to once a night...  I know I can make it faster by porting to C, but
it's that much easier to do in perl.  However, I don't want to waste
cycles running through a preprocessor every time, or running through a
debug routing every time when it's not needed...

Hrm...  more thought needed..  *grin*

---------------------------
Jason H. Frisvold
Senior ATM Engineer
Engineering Dept.
Penteledata
CCNA Certified - CSCO10151622
friz@corp.ptd.net
---------------------------
"Imagination is more important than knowledge. Knowledge is limited.
Imagination encircles the world." -- Albert Einstein [1879-1955]


-----Original Message-----
From: Chas Owens [mailto:cowens@intercall.com] 
Sent: Friday, April 26, 2002 11:47 AM
To: Jason Frisvold
Cc: beginners@perl.org
Subject: RE: Debugging and 'uninitialized value in concatenation'
question

On Fri, 2002-04-26 at 11:44, Jason Frisvold wrote:
> While this appears to be a decent solution, I think I would still
> encounter the same problem that I wanted to avoid...  Every time it
> encounters a CPP statement (#IF DEBUG, #DEFINE, etc) then it still
needs
> to make the proper calls and whatnot...  Whereas in C, since it's
> compiled, the pre-processor strips out the debug junk where
appropriate
> as per your defines...
> 
> I don't think the solution I want exists since this is not a compiled
> language...  Other than writing a pre-processor style program that
> manually strips out the debug stuff I don't want...
> 
> Hrm.. I wonder if I can make a module for CVS that will do this..
> 
> ---------------------------
> Jason H. Frisvold
> Senior ATM Engineer
> Engineering Dept.
> Penteledata
> CCNA Certified - CSCO10151622
> friz@corp.ptd.net
> ---------------------------
> "Imagination is more important than knowledge. Knowledge is limited.
> Imagination encircles the world." -- Albert Einstein [1879-1955]
> 
<snip />

You misunderstand what a source filter is; they _are_ the preprocessors
of the Perl language.  A source filter steps in the the way of the
execution of your perl program and alters it.  Anything hidden by a
false #IF or #IFDEF will not even _be_ in the copy of the Perl program
that perl executes.
 
-- 
Today is Sweetmorn the 43rd day of Discord in the YOLD 3168
All Hail Discordia!

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