I have a Perl script that is getting big, so I want to break it out into multiple scripts. namely, I want to take out some large hash declarations and put them into another file. How do I get the original script to be able to see and use the variables that are now being declared in the other script?
This is driving me nuts because I haven't used Perl in a while and for the life of me can't figure this out
Use a module:
package Literature;
our %Sidekick = (
Batman => "Robin",
Bert => "Ernie",
Don => "Sancho",
);
1;
For example:
#! /usr/bin/perl
use Literature;
foreach my $name (keys %Literature::Sidekick) {
print "$name => $Literature::Sidekick{$name}\n";
}
Output:
$ ./prog
Bert => Ernie
Batman => Robin
Don => Sancho
use Literature qw(Sidekicks); and not have to use the full package name. It'd make the package more complex, but be worth it in the end.
You use modules. Or modulinos.
Make it a module that exports (optionally!) some variables or functions. Look up how to use the Exporter module.
do function to run another Perl script, so you could put all your variable declarations in "myvars.pl" and then do "myvars.pl", but if you do this, it's getting to the point where you should be using a module.Yet another suggestion to use a module.
Modules are not hard to write or use. They just seem hard until you write one. After the first time, it will be easy. Many, many good things come from using modules--encapsulation, ease of testing, and easy code reuse to name a few.
See my answer to a similar question for an example module, with exported functions.
Also, some very smart people in the Perl community like modules so much that they advocate writing apps as modules--they call them modulinos. The technique works well.
So, in conclusion, try writing a module today!
As an addition to the other "use a module" suggestions, if you plan on reusing the module a lot, you will want to get this installed into either your site library (usually under ...(perl install folder)...\site\lib.
If not (perhaps, it has limited reusability outside the script), you can keep it in the directory with your script and import it like so:
use lib './lib'; # where ./lib is replaced with wherever the module actually is.
use MyModule;
