Re^3: use lib and use autouse 'module'

Ah, the directory is known from the beginning. That makes things easier. There's no need to unshift anything, since you can use lib(*).

#!/usr/bin/perl
## untested
use warnings;
use strict;

my ($g_commonMount, $g_moduleDir);
BEGIN {
  $g_commonMount = "/common_mount";
  $g_moduleDir = "$g_commonMount/include";
}
use lib $g_moduleDir;

sub file_watcher {
  while (1) {
    sleep 10, next unless -d $g_moduleDir;

    use autouse 'foo' => qw/foo/;
    foo;
  }
}

file_watcher;
[download]

I'm not particularly proud of the BEGIN block but maybe there's another way to do it. Also, instead of autouse(*), you can use require.

(*) CPAN seems down now, so the links to the modules may be wrong, since they are core and I don't know if one can link to them in the same fashion as any other.

--
David Serrano

Comment on Re^3: use lib and use autouse 'module' Download Code

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Re^4: use lib and use autouse 'module' by cvg2mco (Novice) on Jul 29, 2006 at 01:12 UTC
Thanks for your response. The directory name (only)is known at the beginning. The directory itself gets created (mounted) at a later time. So if this is the case, would the `use lib $g_moduleDir;` [download] give a runtime error? When I tested this syntax in my perl script, It gave a message saying - Empty compile time value given to use lib. But then when I created the include directory, and called `require MY_MODULE;` [download] it loaded the module and gave me access to all the functions and variables defined in the module. I noticed that this is not possible in autouse since we would have to specifiy all the functions and variables in the qw(). Appreciate your comments.	[reply] [d/l] [select]
Re^5: use lib and use autouse 'module' by Hue-Bond (Priest) on Jul 29, 2006 at 12:48 UTC
would the `use lib $g_moduleDir;`give a runtime error? Didn't yesterday when I posted that, and didn't right now. This is what I tried: `use lib '/home/hue/nonexistent'; use autouse 'FOO' => qw/foo/; sleep 10; foo;` [download] Then, in another console, did a `mkdir nonexistent; mv FOO.pm nonexistent`. No warnings or errors from the program, it just run seamlessly. Empty compile time value given to use lib It seems you passed an empty variable to lib. Check it. -- David Serrano	[reply] [d/l]
Re^6: use lib and use autouse 'module' by sshivell (Initiate) on Aug 22, 2006 at 17:51 UTC
>> would the use lib $g_moduleDir;give a runtime* error?* Yes. `use lib $g_moduleDir` would need to be processed at RUNTIME after the $g_moduleDir variable has been set. Unfortunately "use" is processed at compile time and as such $g_moduleDir has not been set which will always create the empty string error that you have seen. You can hard code the path and it will work `use lib 'path/to/my/personal/lib/dir'` *Update: Amusingly enough you can do something like this `#!/usr/bin/perl BEGIN{ use Config::YAML; our $c= Config::YAML->new("/pathtoconfigfile"); our $inc_path = $c->get_includePath; } use lib $inc_path;` [download]	[reply] [d/l] [select]