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in reply to Re^2: How to have OS specific code sections in Perl
in thread How to have OS specific code sections in Perl

Re^3: code that runs (and works) on both Linux and Win32, Devel::AssertOS, Devel::CheckOS, Re: mention a non-installed module in script, Perl::OSType, Module::Loaded 
use if eval { require MIDI::ALSA; MIDI::ALSA->VERSION > 0.01; 1 } , 'M
+IDI::ALSA', ...;
use if not exist $INC{'MIDI/ALSA.pm'}, 'something::else', ...;

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