use File::Temp qw( tempfile ); if ( 0 ) { print STDERR "required\n"; # require FileHandle; } my ($fh, $file) = tempfile( UNLINK => 1 ); $fh->getline; #### $ perl ttrap.t #### $ perl ttrap.t Can't locate object method "getline" via package "FileHandle" at ttrap.t line 12. #### $ perl ttrap.t required #### require FileHandle; #### eval 'require FileHandle'; #### use if $^V ge v5.10.0 && $^V lt v5.11.0, 'FileHandle';