Hi again,
I'm trying to factor out the declaration and setting of a bunch of
variables that a suite of programs will need, as well as defining some
subroutines that will be needed. I've been mainly referencing
Programming Perl 5, but I am mighty confused at this point.
I'm particularly confused about how variables that are declared in my
Package manage to become visible to main (although that's exactly what
I want to happen). As well as the whole issue of what happens when
(at BEGIN, at use, etc.). I feel sure I've greatly complicated
things; as I say, all I want is a way to initialize a handful of
"global" variables, and provide a few subroutines.
When I ran this, here's the output I got:
$ testmod
Hello from Dummy.BEGIN
Hello from testMod.BEGIN
Global symbol "$g_project" requires explicit package name at ./testmod
line 33.
Execution of ./testmod aborted due to compilation errors.
$
Could anyone tell me what subset of Perl modules I need to be
concerned with, and what basic structure to follow, to accomplish this?
'testmod' is the main program; Dummy.pm is the module....
Thanks very much,
Chap Harrison
testmod:
----------
#!/usr/bin/perl
use strict;
use warnings;
#--- BEGIN runs before the rest of testMod gets compiled. One of the
things
# that BEGIN does is to 'use Dummy', which causes Dummy.pm to be
# compiled, which causes certain 'my' variables in Dummy to be
defined.
# These variables somehow become accessible to testMod, which is
odd but nice:
# the main body of testMod references these variables, so they need
to be
# defined at this point.
#---
BEGIN { # This BEGIN runs after Dummy.pm's BEGIN
print "Hello from testMod.BEGIN\n";
#--- The path to my development library is stored as an ENV
variable
use lib "$ENV{LMI_DEVELOP_PATH}"; # This updates @INC early in
runtime
use Dummy qw/start/; # enabling Dummy.pm to be found
}
#--- Main code
my $program = qx(basename $0);
chomp $program;
print "Hello from $program.main\n";
#--- P U L L A N D V A L I D A T E A R G U M E N T S
# This compiles okay, so obviously $g_project is declared at this point.
$g_project = "VA-Orange"; # Simplification; actually passed as cmdline
arg
start(); # Call Dummy initialization routine
print "And now, goodbye from $program\n";
Dummy.pm
---------------
package Dummy;
use strict;
use warnings;
BEGIN {
print "Hello from Dummy.BEGIN\n";
}
use Exporter;
our @ISA = qw/Exporter/;
our @EXPORT_OK = qw/start/;
our $VERSION = "0.0.1";
my $g_project; # Where should I live??
sub start {
#--- C O N S T A N T S A N D G L O B A L S
print "Hello from Dummy::start() - looks like
project='$g_project'\n";
my $gk_env_databases_path = "LMI_DATABASE_PATH";
$ENV{$gk_env_databases_path} = "~/%s"; # fixup env. for purposes
of test
my $g_all_databases_path = $ENV{$gk_env_databases_path};
die "Environment variable '$gk_env_databases_path' is not set. "
. "Need to run lmi-admin.\n"
if ! defined $g_all_databases_path;
lop(\$g_all_databases_path);
my $g_database_path = sprintf $g_all_databases_path, $g_project;
if ( ! -e $g_database_path ) {
print "The district database, $g_database_path, does not exist.\n"
. "Did you specify the project name correctly? ($g_project)\n"
. "\nExiting.\n\n";
exit;
}
}
#--- S U B R O U T I N E S
sub lop {
my $path_ref = shift;
${$path_ref} =~ s[/+$][]; # lop off any trailing slashes
return;
}
1; # Succeeded in loading module
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