Module dependency graph generating scripts.

all-your-modules.hs

#!/usr/bin/env runhaskell
{-# LANGUAGE UnicodeSyntax #-}

import Control.Applicative ((<$>))
import Control.Monad ((<=<))
import Data.List (intercalate)
import System.Environment (getArgs)

import Distribution.ModuleName (components)
import Distribution.PackageDescription (condLibrary, condTreeData, libModules)
import Distribution.PackageDescription.Parse (readPackageDescription)
import Distribution.Verbosity (silent)


main ∷ IO ()
main = getArgs >>= mapM_ (mapM_ putStrLn <=< modules)


modules ∷ FilePath → IO [String]
modules fp = maybe [] (map normalizeModuleName . libModules . condTreeData) . condLibrary <$> readPackageDescription silent fp
 where
  normalizeModuleName = intercalate "." . components

compile-to-graphviz.pl

#!/usr/bin/env perl
use v5.14;
use warnings FATAL => qw(void);


sub main ();
sub parse (@);
sub compile (@);


sub main () {
	my @modules;
	my %modules;
	while (<>) { chomp; push @modules, $_ }
	for my $_ (@modules) { @{$modules{$_}} = parse $_, @modules }
	compile %modules;
}


sub parse (@) {
	(my $module, my @modules) = @_;
	$module =~ s#\.#/#g;
	open(my $HANDLE, "<:utf8", "src/$module.hs") or die "Can't open \"src/$module.hs\": $!";
	my %dependences;
	while (<$HANDLE>) {
		if (/module/) { next }
		for my $candidate (@modules) {
			if (/\s$candidate\s/ ) { $dependences{$candidate} = 1 }
		}
	}
	keys %dependences;
}


sub compile (%) {
	my %modules = @_;
	say "digraph sample {";
	for my $key (keys %modules) {
		for my $module (@{$modules{$key}}) {
			say "\"$key\" -> \"$module\"";
		}
	}
	say "}";
}


main

To get a dependency graph, run
% ./all-your-modules.hs liblastfm.cabal | ./compile-to-graphviz.pl | dot -Tpng > graph.png