You don't need safety from the compiler. You can get safety implemented as humanware. And if that's not enough, yes, you can do some difficult things with Perl to make it also compiler-enforced, at the expense of clarity and maintainability.

If you're working in a place where you can't trust your fellow hacker, quit.

-- Randal L. Schwartz, Perl hacker

Well I am having fun... so no need to quit. Anyway, the situation is basically this:

several functions that I call return nothing, instead the implicitly set variables $x,$y,$z.

I am just worried that at some point $x,$y,$z may also at some point include $a which may be something I'm using and need to keep clean myself.

Does Perl provide any clean way to partition myself from other parts of the program?

Don't call them. Raise a stink. Really.

In the meantime write wrappers for these functions, in the wrappers call, check the implicit variables, and return them. Then when the code can be fixed, less has to be changed. If you can, localize the variables in your wrapper.

And "use strict" to be sure you have everything lexically scoped.

But people like that are a hazard to your code base, nothing more and nothing less.

Ugh. So you're telling me you've got bad code? No amount of Perl Safety will help you.

If $x and $y and $z are in their package, you're safe. If you're telling me you're not using packages, quit, no matter how much fun it is. {grin}

-- Randal L. Schwartz, Perl hacker

I do have to say, I have had to laugh at this thread a little... I've been working with perl off and on the last seven (gosh maybe more...) years and have always enjoyed it... my current employer wanted me to implement some code in perl (I argued for java or c pretty hard... but hey sometimes money talks ;)... anyway I was hoping more somebody would come in with a nice solution and say "here is some neat trick... try this :)"

Instead I've gotten professional help ;)... which is cool, but I'm a *lowly* contractor here *and* too young... hrmmm... so I can't really get in and play the political games to actually fix the problem correctly... I've bugged the guy a few times to help him fix some things, but he's a little put off by having some 'green' punk kid teach him anything. If anything I think it bothers him more that I've been programming longer than him... and more than likely getting paid more. :(

Be that as it may, are there *any* tricks I can pull off to protect myself. I know I could localize variables and all that fun stuff, but I'm more afraid he'll go off and create new variables and such and walk all over my code. It has happened a few times to me and unfortunately talking to his manager hasn't helped any because he is basically given free reign to do whatever he wants.

So can I do something weird like localize main:: or somehow seperate his memory space from mine without his code knowing about it? I really don't care to spend the time to re-write any of his code, especially since I don't want to be walking on any toes.

I've already ran into enough problems now that I am trying to get him to fix anyway... so this isn't highest on my priority list to get him to fix... I'd rather get him focusing any time he can give me to *not* crashing out on me and killing my programs that use his code.

Oh well... I guess this thread has become more 'off topic' than what *I* expected at least :)... guess I'll have to see what I can do on my end to get this engineer to help me out :).

Use package as a buffer.
Write a package of wrappers around his functions, and then only export those functions from the wrapper. There is no way for a module's code to run over yours if you don't import it into your package. Most of us (well, me anyway) use the main package without bothering to name it. Java doesn't let you get away with this, but since you argued for using Java, maybe you should adopt this habit. Then don't import anything into your named package that you didn't write.

Does this make sense or is my blood sugar too low?

Instead I've gotten professional help ;)... which is cool, 
but I'm a *lowly* contractor here *and* too
young... hrmmm... so I can't really get in and play the 
political games to actually fix the problem correctly...
I've bugged the guy a few times to help him fix some 
things, but he's a little put off by having some 'green'
punk kid teach him anything. If anything I think it 
bothers him more that I've been programming longer than
him... and more than likely getting paid more. :(


###########

This is precisely the culture that I work so hard to avoid,
yet landing there seems to be unavoidable.  

If you have a valid point ( and it looks like you do based
on your description of the problem ), then I suggest you
become an evil, manipulative bastard by asking the following
question:

"What am I missing?"

This insidious little question is extremely confrontational
because it forces them to explain to YOU exactly how their
way will work.  Their explanation will not make sense, so
be sure to ask it in the presence of at least 1 ally.  If
they dodge, repeat the question.

If they dodge, repeat the question.

If they dodge, repeat the question.

If they dodge, repeat the question.

If they dodge again, say "Excuse me, but I really do not
understand what you are doing here.  Can you please help
me understand what you are trying to do and how I can
succeed with your code?"

If they don't help you, then that is a refusal to help
a coworker whose work depends upon their success.  At that
point, maybe some sort of third party intervention shall 
be required.  Be sure to present it as in the context of
how you do not understand what the other person is doing and
they are refusing to work with you to solve the problem.

Also, be prepared to leave if your company is extremely sick
culturally.  They will not like this.  Having allies 
present is extremely important.  This is a CYA for your
presentation to HR...if 3 people complain to HR, it will 
probably be believed.  If 4 people complain to HR, it shall
be believed and action will be taken.

##########

On a lighter note:

while ( $dodge ) {

   print "What am I missing?\n";

} # while

--moo

Instead I've gotten professional help ;)... which is cool, but I'm a *lowly* contractor here *and* too young... hrmmm... so I can't really get in and play the political games to actually fix the problem correctly... I've bugged the guy a few times to help him fix some things, but he's a little put off by having some 'green' punk kid teach him anything. If anything I think it bothers him more that I've been programming longer than him... and more than likely getting paid more. :( ########### This is precisely the culture that I work so hard to avoid, yet landing there seems to be unavoidable. If you have a valid point ( and it looks like you do based on your description of the problem ), then I suggest you become an evil, manipulative bastard by asking the following question: "What am I missing?" This insidious little question is extremely confrontational because it forces them to explain to YOU exactly how their way will work. Their explanation will not make sense, so be sure to ask it in the presence of at least 1 ally. If they dodge, repeat the question. If they dodge, repeat the question. If they dodge, repeat the question. If they dodge, repeat the question. If they dodge again, say "Excuse me, but I really do not understand what you are doing here. Can you please help me understand what you are trying to do and how I can succeed with your code?" If they don't help you, then that is a refusal to help a coworker whose work depends upon their success. At that point, maybe some sort of third party intervention shall be required. Be sure to present it as in the context of how you do not understand what the other person is doing and they are refusing to work with you to solve the problem. Also, be prepared to leave if your company is extremely sick culturally. They will not like this. Having allies present is extremely important. This is a CYA for your presentation to HR...if 3 people complain to HR, it will probably be believed. If 4 people complain to HR, it shall be believed and action will be taken. ########## On a lighter note: while ( $dodge ) { print "What am I missing?\n"; } # while --moo

Please don't misread my "quit" as literally "don't check in for work tomorrow". What I mean is change the situation. Work whatever way you can to make it different, because it's dangerous the way it is. "quit" doing business as you've been doing it.

If you can't find a common purpose, and you've tried to find alignment, then you literally do need to find a different job, or be miserable. There's no third option.

-- Randal L. Schwartz, Perl hacker

Assuming your global using package looks like this...

--- Global.pm ---
$GLOBAL = 'Bad bad global';
sub dumbproc {
        $GLOBAL = 'Still sucks';
}
[download]

Then you can hide the globals like this...

--- HideGlobals.pm ---
package HideGlobals;
use vars qw( @ISA @EXPORT_OK );
require Exporter;
@ISA = qw( Exporter );

use Globals;

@EXPORT_OK = qw( &hidden_dumbproc );

sub hidden_dumbproc {
        dumbproc(@_);
        return $GLOBAL;
}
1;
[download]

Here is my test code...

use HideGlobals qw( &hidden_dumbproc );

print $HideGlobals::GLOBAL, "\n";

print &hidden_dumbproc, "\n";
[download]

Write your own code inside a package, use strict in your code, and explicitly reference the globals in package "main" which they seem to have claimed for themselves. As long as you're in a different package, and don't create any globals in main::, you should be Okay, no? (until they step on each others toes instead of yours... but to a certain extent you're never going to be able to fully insulate yourself form stupid programs or programmers)

Alan