[erlang-questions] Retrieving the dependencies of a module

[Lutz Behnke]

Not really. Instead it deepens my confusion, as it reports the same 
function as missing in plumtree as it does in my code, despite the CT 
tests of plumtree working.

mfg lutz

Am 24.07.2018 um 17:16 schrieb Ivan Uemlianin:
> Does xref do what you need?
> 
>      http://erlang.org/doc/apps/tools/xref_chapter.html
> 
> Ivan
> 
> 
> On 24/07/2018 15:33, Lutz Behnke wrote:
>> Hi there,
>>
>> I am trying to find out what other modules the functions in a given 
>> module are calling. Is there a standard mechanism to do so?
>>
>> I have the following problem:
>>
>> In one application build with rebar3:
>>
>> app_one/src/a.erl:
>> -module(a)
>> f1() -> b:f2().
>>
>> in the other application, also build with rebar3:
>>
>> app_two/src/b.erl:
>> -module(b)
>> f2() -> c:f3().
>>
>>
>> The module c is nowhere defined in either application one, two, or the 
>> dependencies either pulls.
>>
>> When I run the tests of application two everything works, when I try 
>> to call the code from the module a, I get:
>>
>>  {failed_to_start_child,b,
>>           {undef,
>>               [{c,f3,[],[]},
>>                {b,f2,1,[{...}|...]},
>>                {gen_server,init_it,2,[...]},
>>                {gen_server,init_it,6,...},
>>                {proc_lib,init_p_do_apply,...}]}}}
>>
>> application two is specifically my fork of plumtree:
>>   https://github.com/timadorus/plumtree
>>
>> Therefore I am trying to understand what is actually placed in the 
>> beam, or what modules are accessed from b (aka 
>> plumtree_metadata_hashtree) to see where the working code in the test 
>> is comming from).
>> I would assume that there is some code_transform going on, but cannot 
>> find any in the rebar configuration.
>>
>> Any help appreciated.
>>
>> mfg lutz
> 


-- 
Lutz Behnke
Hochschule für Angewandte Wissenschaften Hamburg,
Labor für Allgemeine Informatik,

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