In my line of work, it seems that more often that not I write a script that contains functionality that would be useful to have as part of a module as well. While I could certainly put all of my useful code in a module and then write a short wrapper that would call a routine in the module to kick off processing, I think that it would be slick if I could make it all happen in the module file. For example, I have a module called checkem.pm that starts off as follows: 
#!/bin/sh

eval "exec /usr/software/bin/perl5.8.0 -I`pwd` -Mcheckem -e main $*"
    if $running_under_some_shell;

package main;

sub main {
    print "Hello from main\n";
    <useful code here>
}

[download]
This is all well and good, but it requires me to be in the directory where checkem.pm lives or to hardcode the path to checkem.pm in the -I argument. Neither of these is horribly appealing to me. It would be really nice if I could use the same code in each module. I was trying to do something more like: 
#!/bin/sh

DIR=`dirname $0`
BASE=`basename $0 | sed -e 's/\.pm\$//'`
eval "exec /usr/software/bin/perl5.8.0 -I$DIR -M$BASE -e main $*"
    if $running_under_some_shell;

package main;
...

[download]
but of course Perl doesn't like the DIR= and BASE=lines. Adding if $running_under_some_shell to the DIR= and BASE= lines doesn't help either and -w didn't provide any useful insight. Any suggestions would be appreciated. It would also be nice if I didn't have to name things module.pm too ;-)

In reply to Running a module? by bschmer

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