in reply to Asking a question in Makefile.PL

If you want to control the process yourself remember that Makefile.PL is just perl so before the call to WriteMakefile do whatever you want: 

use ExtUtils::MakeMaker;

eval{require Some::Module};
if ($@) {
    my $reply = prompt("Some::Module not installed. Install (Y/n)", "Y
+");
    install("Some::Module") unless $reply =~ m/n/i;
}

sub install {
    my $module = shift;
    eval{require CPAN};
    die "Aaaaagh! $@\n" if $@;
    CPAN::Shell->install($module);
}

WriteMakefile(
    ...
);

[download]

Update: In line with grinders post changed to EUMM prompt routine.

Replies are listed 'Best First'.
Re^2: Asking a question in Makefile.PL
by grinder (Bishop) on Apr 20, 2008 at 09:41 UTC

    And to back up what bingos says. NO, don't write your own prompt routine. You already have one in the EUMM distribution, and as a bonus it will play nicely with unattended installations.

    • another intruder with the mooring in the heart of the Perl

[reply]
Re^2: Asking a question in Makefile.PL
by bingos (Vicar) on Apr 20, 2008 at 08:30 UTC

    NO, please don't invoke CPAN in Makefile.PL

    It is extremely bad practice. It plays havoc with CPANPLUS based CPAN tester rigs ( like mine ), and for people who don't use CPAN but use CPANPLUS for installing modules.

    Update

    The best way is to just let CPAN/CPANPLUS deal with installing the module for you as a prereq.

    use ExtUtils::MakeMaker;

my %prereqs = ( 
  "Blah::Blah" => 0,
  "Foo::Bar"   => 1.0,
);

eval{require Some::Module};
if ($@) {
    my $reply = prompt("Some::Module not installed. Install (Y/n)", "Y
+");
    $prereqs{"Some::Module"} = 0 unless $reply =~ m/n/i;
}

WriteMakefile(
      PREREQ_PM => \%prereqs,
);

    [download]
[reply]
[d/l]

      While I'll accept it might not be best practice or suit testing rigs I would be interested to know what the preferred alternatives are.

[reply]
      Okay, but what would be the alternative in this case? Could I check if CPANPLUS is what's being used and use that or use CPAN instead?
[reply]

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