-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Hello there
My application consists of several files. Some of them are to be run as
CGI scripts, the others from command line. There is also a "common" file
with constants and shared routines.
The question is: what is the most standard way to export constants from
that common file so that they could be used in the other files?
Here is a minimal example:
- -------- one.pl --------
package MyPackage;
use warnings;
use strict;
use constant {
~ MY_FIRST_CONSTANT => 'hello world!'
};
*MY_SECOND_CONSTANT = [1, 3, 7];
*MY_SECOND_CONSTANT = \729;
sub routine1 {
~ print "Hello from routine1! $MyPackage::MY_SECOND_CONSTANT\n";
}
# This is to satisfy require()
1;
- -------- two.pl --------
package MyPackage;
use warnings;
use strict;
require 'one.pl';
print 'The 1st constant is: ' . MyPackage->MY_FIRST_CONSTANT . "\n";
print 'The 2nd constant is: ' . *MY_SECOND_CONSTANT . "\n";
print ' SCALAR: ' . ${*MY_SECOND_CONSTANT{SCALAR}} . "\n";
print ' ARRAY: ' . join(', ',
@{*MY_SECOND_CONSTANT{ARRAY}}) . "\n";
MyPackage->routine1;
- ----------------
This produces output like this:
$ perl ./two.pl
The 1st constant is: hello world!
The 2nd constant is: *MyPackage::MY_SECOND_CONSTANT
~ SCALAR: 729
~ ARRAY: 1, 3, 7
Hello from routine1! 729
Funny thing is that in two.pl MyPackage->MY_FIRST_CONSTANT works, but
neither of these:
print '' . MY_FIRST_CONSTANT . "\n";
print '' . MyPackage::MY_FIRST_CONSTANT . "\n";
Bareword "MY_FIRST_CONSTANT" not allowed while "strict subs" in use at
./two.pl line ***.
Execution of ./two.pl aborted due to compilation errors.
So I suspect that although I managed to solve the problem, the solution
with MyPackage->MY_FIRST_CONSTANT is a bug in Perl or something?? Why
should I be able to call the constant subroutine, but not be able to
refer to the constant "as is"??
Why should I even bother with all these, since I am using only 1 package
MyPackage? The documentation says package is namespace is symbol table.
Why does MY_FIRST_CONSTANT work "as is" in one.pl, and not in two.pl?
I am using Perl v5.8.8.
STF
=======================================================================
http://eisenbits.homelinux.net/~stf/ . My PGP key fingerprint is:
9D25 3D89 75F1 DF1D F434 25D7 E87F A1B9 B80F 8062
=======================================================================
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (GNU/Linux)
Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org
iD8DBQFJpSAQ6H+hubgPgGIRAoYHAJ4uRiGGwlAbjB3whHx8nDOZCN58QwCdHZTA
Y7Anj2S1iXe93mES2d19REY=
=iwf7
-----END PGP SIGNATURE-----
--
To unsubscribe, e-mail: beginners-unsubscr...@perl.org
For additional commands, e-mail: beginners-h...@perl.org
http://learn.perl.org/
