package main; BEGIN { my $isScript= ! caller(2); sub _isScript() { $isScript } } if( _isScript ) { require CGI; my $q= CGI->new(); # ... } undef &_isScript; #### package main; unless( caller ) { my $code= do { local($/); }; my $file= __FILE__; my $line= __LINE__ + 5; eval "\n# line $line $file\n$code; 1" or die "$@\n"; } __END__ use CGI; # ... __END__