My Devel::Examine::Subs can list subs within files.

Single file example:

use warnings;
use strict;

use Devel::Examine::Subs;

my $des = Devel::Examine::Subs->new(file => 'lib/Devel/Examine/Subs.pm
+');

my $subs = $des->all;

print "$_\n" for @$subs;
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Output:

BEGIN
new
all
has
missing
lines
module
objects
search_replace
replace
inject_after
inject
remove
order
backup
add_functionality
engines
pre_procs
post_procs
run
valid_params
_cache
_cache_enabled
_cache_safe
_clean_config
_clean_core_config
_config
_file
_params
_read_file
_run_directory
_run_end
_write_file
_core
_pre_proc
_proc
_post_proc
_engine
_pod
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You can also do entire directory structures:

use warnings;
use strict;

use Devel::Examine::Subs;

my $des = Devel::Examine::Subs->new(file => '.');

my $data = $des->all;

for my $file (keys %$data){
    print "$file:\n";
    for my $sub (@{ $data->{$file} }){
            print "\t$sub\n";
    }
}
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Snipped example output:

t/test/files/sample.pm:
    one
    one_inner
    one_inner_two
    two
    three
    four
    function
    five
    six
    seven
    eight
examples/write_new_engine.pl:
    dumps
lib/Devel/Examine/Subs/Sub.pm:
    BEGIN
    new
    name
    start
    end
    line_count
    lines
    code
lib/Devel/Examine/Subs/Preprocessor.pm:
    BEGIN
    new
    _dt
    exists
    module
    inject
    replace
    remove
    _vim_placeholder
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The software does a ton of useful things, but these are examples of the most basic functionality. It does not know how to see sub dependencies of other subs. However, I do have another software that does, however, it is intrusive (it actually writes into the Perl files, and you have to run the software to get usable trace information (ie. if you don't call all scenarios, it may not find all flows). I don't have the time at the moment to write a proper scenario for that, but have a look at Devel::Trace::Subs if you're interested. If you don't come up with anything else by morning, I'll create a good example.