The Perl Short Questions Megathread: executable line noise

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > The Cavern of COBOL > The Perl Short Questions Megathread: executable line noise

There Will Be Penalty: May 18, 2002; Makes a great pet!

Ninjew posted:

Stabby McDamage posted:
- Subroutines can be passed as variables ("closures").

Actually, this isn't what a closure is. *snip*

Nice clarification. Also, whether or not your language supports closures, the concept of passing subroutines (or subroutine references) as variables is properly termed "higher-order programming".

:eng101:

# ¿ Oct 25, 2007 19:38

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# ¿ Apr 30, 2024 01:41

There Will Be Penalty: May 18, 2002; Makes a great pet!

TiMBuS posted:

But then I would have to undef $\ when using print for other needs. =(

code:

print "fred";        # doesn't print a newline
{
    local $\ = "\n"; # can't use my here
    print "barney";  # prints a newline
}
print "wilma";       # doesn't print a newline

# ¿ Jan 15, 2008 20:15

There Will Be Penalty: May 18, 2002; Makes a great pet!

satest4 posted:

A subroutine definition can refer to variables that exist in the surrounding scope.

That sort of thing is called a closure. :eng101:

# ¿ Sep 22, 2008 18:02

There Will Be Penalty: May 18, 2002; Makes a great pet!

ashgromnies posted:

loving ace. I always forget about queues working in Perl all the time

I also didn't know about File::Basename... is there a good core module reference anywhere?

perlmodlib(1)

# ¿ Nov 1, 2008 21:15

There Will Be Penalty: May 18, 2002; Makes a great pet!

Not a short question, but Perl was released 21 years ago today.

Yay Perl!

# ¿ Dec 19, 2008 03:28

There Will Be Penalty: May 18, 2002; Makes a great pet!

Sartak posted:

Found an interesting bug today at work. It would have slipped under my nose if other parts of the code had looser validation. What's the bug?

code:

my %is_special = map { $_ => 1 } qw/user project transaction/;

sub create_record {
    my $self = shift;
    my $type = shift;

    if ($is_special{$type} || ($type =~ /^(.*)s$/ && $is_special{$1})) {
        $type = $1 || $type;
        return $self->create_special_record($type, @_);
    }
    
    return $self->create_mundane_record($type, @_);
}

if $is_special{$type} is true then $1 was preserved from the most recent regex match instead of being undefined or something, right?

# ¿ Feb 3, 2009 01:08

There Will Be Penalty: May 18, 2002; Makes a great pet!

Triple Tech posted:

Does the bitwise-and bind too tightly causing you to regexp bind on a "1"??

=~ binds tighter than &&. See perlop(1). And && is not a bitwise AND.

# ¿ Feb 3, 2009 01:14

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# ¿ Apr 30, 2024 01:41

There Will Be Penalty: May 18, 2002; Makes a great pet!

FeloniousDrunk posted:

code:

    $$a{'000', 1} = $lea;

Read the perlvar(1) documentation under $;.

# ¿ Mar 4, 2009 17:27

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