BEGIN { require Module; Module->import( LIST ); } #### use Module (); #### BEGIN { require Module } #### #!/usr/bin/perl use strict; use warnings; BEGIN { print ">>> About to execute 'use LoadMe;' <<<\n"; } use LoadMe; BEGIN { print ">>> LoadMe was loaded <<<\n"; } print "***** See? No code in LoadMe is executed! *****\n"; #### package LoadMe; use strict; use warnings; INIT { print "LoadMe: INIT is evaluated\n"; system "echo Would I run rm -rf / ?"; } CHECK { print "LoadMe: CHECK is evaluated\n"; system "echo Check check, is this thing on?"; } UNITCHECK { print "LoadMe: UNITCHECK is evaluated\n"; system "echo Luckily, format C: does not work on linux"; } BEGIN { print "LoadMe: BEGIN is evaluated\n"; system "echo what could go wrong?"; } END { print "LoadMe: END is evaluated\n"; system "echo Good bye cruel world"; } sub foo { print "LoadMe: foo\n"; } sub import { my $class=shift; print "LoadMe: import called as ${class}->import(",join(',',@_),")\n"; system "echo Oh well, no smart comment here"; } print "LoadMe: Module initialisation\n"; system "echo Perl is fully working and can run arbitary code, including external programs"; 1; # or any other non-false value #### /tmp/use-demo>perl demo.pl >>> About to execute 'use LoadMe;' <<< LoadMe: BEGIN is evaluated what could go wrong? LoadMe: UNITCHECK is evaluated Luckily, format C: does not work on linux LoadMe: Module initialisation Perl is fully working and can run arbitary code, including external programs LoadMe: import called as LoadMe->import() Oh well, no smart comment here >>> LoadMe was loaded <<< LoadMe: CHECK is evaluated Check check, is this thing on? LoadMe: INIT is evaluated Would I run rm -rf / ? ***** See? No code in LoadMe is executed! ***** LoadMe: END is evaluated Good bye cruel world /tmp/use-demo> #### /tmp/use-demo>perl -cw demo.pl >>> About to execute 'use LoadMe;' <<< LoadMe: BEGIN is evaluated what could go wrong? LoadMe: UNITCHECK is evaluated Luckily, format C: does not work on linux LoadMe: Module initialisation Perl is fully working and can run arbitary code, including external programs LoadMe: import called as LoadMe->import() Oh well, no smart comment here >>> LoadMe was loaded <<< LoadMe: CHECK is evaluated Check check, is this thing on? demo.pl syntax OK /tmp/use-demo>perl -cw LoadMe.pm LoadMe: BEGIN is evaluated what could go wrong? LoadMe: UNITCHECK is evaluated Luckily, format C: does not work on linux LoadMe: CHECK is evaluated Check check, is this thing on? LoadMe.pm syntax OK /tmp/use-demo>