Erlang Parameterized Modules

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Parameterized Modules also called Abstract Modules or Tuple Modules.

From Stack Overflow

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-module(foo).

-compile(export_all).

new(Bar) -> {foo, Bar}.

get({foo, Bar}) -> Bar.
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1> c(foo).
{ok,foo}
2> Foo = foo:new(bar).
{foo,bar}
3> Foo:get(). 
bar

From Elang Central

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-module(test, [A, B]).

-export([get_a/0, get_b/0]).

get_a() -> A.

get_b() -> B.
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1> c(test).
{ok,test}
2> test:module_info().
[{exports,[{get_a,1},
           {get_b,1},
           {new,2},
           {instance,2},
           {module_info,0},
           {module_info,1}]},
 {imports,[]},
 {attributes,[{vsn,[44232957561630721650243949532469790901]},
              {abstract,[true]}]},
 {compile,[{options,[]},
           {version,"4.6.4"},
           {time,{2010,2,21,20,52,18}},
           {source,"/home/bile/code/erlang/test/test.erl"}]}]
3> T = test:new("This is A", "This is B").
{test,"This is A","This is B"}
4> T:get_a().
"This is A"
5> T:get_b().
"This is B"
6> T:module_info().
** exception error: bad argument
     in function  erlang:get_module_info/2
        called as erlang:get_module_info(test,{test,"This is A","This is B"})
     in call from test:module_info/1
7> test:instance("A","B").
{test,"A","B"}
8>

Ending

栗子分别来自于
http://stackoverflow.com/questions/40539120/are-tuple-modules-an-officially-documented-feature-of-the-language
和
http://www2.erlangcentral.org/wiki/?title=Parameterized_Modules

官方并不建议使用这种方式。