It’s for backwards compatibility. Perl 4 didn’t have strict at all, and there are most likely still scripts out there originally written for Perl 4 that still work fine with Perl 5. Making strict automatic would break those scripts. The situation is even worse for one-liners, many of which don’t bother to declare variables. Making … Read more
From Perlfaq8: You’re confusing the purpose of system() and backticks (“). system() runs a command and returns exit status information (as a 16 bit value: the low 7 bits are the signal the process died from, if any, and the high 8 bits are the actual exit value). Backticks (“) run a command and return … Read more
Check file permissions. I had exactly the same error on a Linux machine with the wrong permissions set. chmod 755 myfile.pl solved the problem.
You can do this in vim using a Dictionary: :%s/quick\|lazy/\={‘quick’:’slow’,’lazy’:’energetic’}[submatch(0)]/g This will change the following text: The quick brown fox ran quickly next to the lazy brook. into: The slow brown fox ran slowly next to the energetic brook. To see how this works, see :help sub-replace-expression and :help Dictionary. In short, \= lets you … Read more
The short answer is that they’re quite heavy (you can’t launch 100+ of them cheaply), and they exhibit unexpected behaviours (somewhat mitigated by recent CPAN modules). You can safely use Perl ithreads by treating them as independent Actors. Create a Thread::Queue::Any for “work”. Launch multiple ithreads and “result” Queues passing them the (“work” + own … Read more
You’re confused because you think = is a single operator while it can result in two different operators: a list assignment operator or a scalar assignment operator. Mini-Tutorial: Scalar vs List Assignment Operator explains the differences. my $b = (33,22,11); —————— Scalar assign in void context. ———- List literal in scalar context. Returns last. my … Read more
Old Answer (still applies unless you are using Visual Studio Update 1 RTM (2015) or later) In short. No, there doesn’t seem to be a good plugin for it. If you use Perl rarely, I would recommend sticking with Visual Studio for Microsoft languages and Padre for Perl. However, if you use Perl as much … Read more
You can use a negative lookahead (documented under “Extended Patterns” in perlre): /^\/(?!bob\/)/
Because in Haskell, we have laziness & guarded recursion and tail call optimization and Perl has neither. This essentially means that every function call allocates a set amount of memory called “the stack” until the function returns. When you write recursive code, you build up a huge amount of memory because of these nested function … Read more
Let’s say I have a package MyPackage that uses @EXPORT. #this is MyPackage.pm package MyPackage; @EXPORT = qw(do_awesome_thing); sub do_awesome_thing { … } sub be_awesome { … } Now, when I use MyPackage in my code, #this is myscript.pl use MyPackage; do_awesome_thing(); #works be_awesome(); #doesn’t work MyPackage::be_awesome(); #works do_awesome_thing gets automatically exported to my code … Read more