perl -d:Modlist=options script.pl
          perl -MDevel::Modlist=options script.pl # equivalent

##</code><code>##

#!perl
  #use strict;  #commented to not pollute %INC
  #use warnings;#commented to not pollute %INC

my $file = $ARGV[0];
my $content = do { open my $fh, '<', $file or die $!; local $/; <$fh> };
my $begin =<<'THEEND';

UNITCHECK {
    no strict; # access $VERSION by symbolic reference
    no warnings qw (uninitialized);
    print map {
        s!/!::!g;
        s!.pm$!!;
        sprintf "%-20s %s\n", $_, ${"${_}::VERSION"}
    } sort keys %INC;
    exit;
};

THEEND

eval $begin.$content;
print $@ if $@;


##</code><code>##

perl -c -e "BEGIN{print qq(1-begin\n)};
            UNITCHECK {print qq(2-unitcheck\n)};
            CHECK {print qq(3-check\n)};
            INIT {print qq(4-init\n)};
              print qq(5-main\n);
            END{print qq(6-end\n)}"

__OUTPUT__
1-begin
2-unitcheck
3-check
-e syntax OK

# the same code without -c

__OUTPUT__
1-begin
2-unitcheck
3-check
4-init
5-main
6-end