[ale] perl question

[Geoffrey Myers]

Brian Mathis wrote:
> On Tue, Jan 17, 2012 at 11:22 AM, Derek Atkins <warlord at mit.edu> wrote:
>> Geoffrey Myers <lists at serioustechnology.com> writes:
>>
>>> Oh the loop works as defined, it's just that the value is not passed to
>>> the sub bar()  My expectation was that since the call to bar() was
>>> inside the loop, that $foo would be accessible within the sub.
>> Alas, it doesn't work that way.  PERL doesn't scope variables that way.
>> You would need to define a global and assign it, or you would need to
>> pass it as a variable to the sub.
>>
>> -derek
> 
> 
> It doesn't, and shouldn't, work that way in /any/ programming
> language.  The problem is definitely that the variables are never
> passed to the sub, and trying to do it through bash-style globals is
> very, very bad form (bash is not a programming language).
> 
> The first thing you should be doing in all Perl programs is "use
> strict;" before anything else.  That would have caught this error
> right away.

I should provide some background.  We ALWAYS:

use strict;
use warnings;

In all our code.  I am making changes to someone else's code and came 
across this solution.  Although I agree, it's not the way to do it, I 
was trying to understand why it did not work.

I'm trying to understand why that code does not work, but this does:

#!/usr/bin/perl

use strict;
use warnings;


my $foo = "stuff";

bar();

sub bar
{
     printf "%s\n", $foo;
}


> 
> 
> ❧ Brian Mathis
> 
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-- 
Until later, Geoffrey

"I predict future happiness for America if they can prevent
the government from wasting the labors of the people under
the pretense of taking care of them."
- Thomas Jefferson