Hi Joseph:
Thanks very much for the feedback. Unfortunately for me, I've been
totally swamped with tasks totally unrelated to Perl. I've had virtually
no time to spend on this. I hope to have time this weekend to look at
Perl related activities (my wife may have other thoughts about that
however :-))
Anyway, here is the context of what I was trying to learn how to do.
Basically, I wanted to know how to put a receipient's name into a canned
letter. Like this.
$name = "Joe Blow"
The canned letter template:
Dear $name:
Your are a very nice person.
After running the program, the letter would be sent like this:
Dear Joe Blow:
You are a very nice person.
I'll try to cleanup & send the actual code I use for this. After seeing
the actual code, I would be very interested in getting your expert advice
and opinion. If indeed I'm not doing this in a proper way, I will
certainly want to correct that.
Thanks again for providing the feedback. I greatly appreciate your taking
the time to help in advancing my Perl knowledge. I just wish I had more
time to spend with Perl. It's such a fun language !
- Stuart
"R. Joseph Newton" <[EMAIL PROTECTED]>
01/30/2004 12:50 AM
To
[EMAIL PROTECTED]
cc
[EMAIL PROTECTED]
Subject
Re: How to put a variable value into a text file
[EMAIL PROTECTED] wrote:
>
> Here's what it prints: My name is $name.
>
> Here's the testmessage.txt file: My name is $name.
Hi Stuart,
I think that there is a conceptual problem here. This really isn't the
appropriate way to get modular code into a program. Programming would be
a
dangerous business indeed if our programs automatically interpolated
variable
names encountered in text data.
The techncal concerns are relatively minor compared to the conceptual
problems. I would recommend against pursuing this path of inquiry,
because
the mixing of data and program code is inherently a seed of error and
system
instability. It also can be an easy route for subverting system security.
Data and program structures should not be mixed without compelling reason,
and
a high-end understanding of the potential consequences. New students of
programming should avoid it entirely, IMHO.
Can you think of a real-world situation where you would want to put
program
code in a data file? If you want modular functionality, Perl does have
some
very approachable protocols for creating packages of such functionality,
including the option of creating instantiable objects to reflect
real-world
concepts. For this, you might want to start with:
perldoc perlmod
perldoc perlobj
but first, for necessary background, read
perldoc perlref
or at least
perldoc perlreftut
Use the language features designed for linking functions, though.
Hand-hcking
mixed code and data will only get you in trouble.
Joseph
