chrstphrchvz has asked for the wisdom of the Perl Monks concerning the following question:
Howdy Monks,
I have a test that I would like to skip if a requisite .ph file is not available, so I considered using:
eval { require 'sys/ioctl.ph' }; # skip if $@ contains # "Can't locate 'sys/ioctl.ph' in @INC (did you run h2ph?)"
However, doing require 'sys/ioctl.ph' from the test script "breaks" the module.
Here is a simplified equivalent:
funnybusiness.pm:
package funnybusiness; use warnings; use strict; sub s1 { require 'sys/ioctl.ph'; print FIONREAD() . "\n"; # should print some number } 1;
test.pl:
use warnings; use strict; use funnybusiness; #require 'sys/ioctl.ph'; funnybusiness::s1;
Assuming sys/ioctl.ph is available, running test.pl prints the value of FIONREAD in sys/ioctl.h. But uncommenting the require statement in test.pl causes an Undefined subroutine &funnybusiness::FIONREAD error.
I can prevent the error by having funnybusiness.pm use main::FIONREAD() instead (edit: that breaks normal code that doesn't have the require statement). But I would like to understand why the require statement in the script is "breaking" the module: whether there's some bad assumption that funnybusiness.pm makes about what FIONREAD() can mean, or if the script should somehow know better than to do a require that might be done by the module, or if this behavior might be a bug/limitation/feature, etc.
(Actual module for anyone curious:
- require statement in module: https://github.com/chrstphrchvz/perl-tcl-ptk/blob/dbf896f71e/lib/Tcl/pTk/Widget.pm#L2149
- FIONREAD() usage that breaks: https://github.com/chrstphrchvz/perl-tcl-ptk/blob/dbf896f71e/lib/Tcl/pTk/Widget.pm#L2186
The module makes use of AUTOLOAD, meaning I get something more wacky than a Undefined subroutine error.)