[erlang-bugs] dialyzer typename/0 and typename/1 names are treated the same?

[ノートン ジョーセフ ウェイ ン]

Given the sample module below, dialyzer reports that f_datum is already defined.

This behaviour is strange to me because I'm expecting f_datum/0 and f_datum/1 to be treated as two independent types.  Is this a bug or specification?

thanks,

Joe N.


NG case:

$ dialyzer --src --plt ~/.dialyzer_plt.R15B03  src/foobar.erl 
  Checking whether the PLT /Users/norton/.dialyzer_plt.R15B03 is up-to-date... yes
  Proceeding with analysis...
dialyzer: Analysis failed with error:
Could not scan the following file(s): [{"/Users/norton/appfoobar/src/foobar.erl",
                                        "Type f_datum already defined\n"}]
Last messages in the log cache:
  Reading files and computing callgraph… 


$ cat src/foobar.erl 

-module(foobar).

-type foo() :: foo.
-type bar(T) :: list(T).

-type f_datum(T) :: foo() | bar(T).
-type f_datum() :: f_datum(f_datum()).



OK case:

$ dialyzer --src --plt ~/.dialyzer_plt.R15B03  src/foobar.erl 
  Checking whether the PLT /Users/norton/.dialyzer_plt.R15B03 is up-to-date... yes
  Proceeding with analysis... done in 0m26.28s
done (passed successfully)


$ cat src/foobar.erl 

-module(foobar).

-type foo() :: foo.
-type bar(T) :: list(T).

-type f_datum(T) :: foo() | bar(T).
-type f_datums() :: f_datum(f_datums()).



Erlang/OTP version info:

$ erl -v
Erlang R15B03 (erts-5.9.3.1) [source] [64-bit] [smp:2:2] [async-threads:0] [hipe] [kernel-poll:false]

Eshell V5.9.3.1  (abort with ^G)
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