require mystery

[Pstack]

I cannot seem to successfully require "File::Path" despite that use "File::Path" works fine.

When I require "File::Path" the runtime error is that it is not in @INC, despite that the correct path does seem to be located there "/..../5.8.7/File/Path.pm".

I am wondering if there is some particular reason that File::Path may not be able to be required? Or do I need to do a bit more digging on the problem?

cheers

Pstack

[ikegami]

Going on a hunch since you provided neither the code causing the error nor the resulting error message,

use File::Path;           # ok
require File::Path;       # ok
require "File/Path.pm";   # ok
require "File::Path";     # Error!

[Pstack]

I followed your hunch to look deeper, as it seemed line 2 should have failed for me, even if there had been a prior use.

my $pathtool = "File::Path";
eval {require $pathtool}; # FAILS
if ($@) {print $@;} # "No File::Path in @INC"

eval "require $pathtool"; # OK
eval {require File::Path}; # OK
eval {$pathtool->import("mkpath")}; # OK

Clearly $pathtool wont work in the FIRST block eval where the bareword will, but will work in the SECOND block eval. A subtle trap for young players! But I am relieved. Thanks for your help.

Pstack

[Corion]

No:

require $pathtool;

is exactly the same as

require "File::Path";

which fails. Your other attempt,

eval "require $pathtool";

evaluates the string, which then looks like

require File::Path;

which succeeds. Consider using the following code if you want a dynamic module loader:

sub require_package {
    for (@_) {
        (my $file = $_) =~ s-::|'-/-g;
        require "$file.pm";
    };
};

Other alternatives which I recommend against are UNIVERSAL::require and Module::Load because they both hide fatal errors from you, for example compilation errors in the required modules.

Maybe you might want Module::Pluggable for a plugin system.

[clinton]

       require mystery;

Ahhh, the cure for a mundane life...

[Anonymous Monk]

Tsk tsk, you have to import before you're cured :)