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digitalmars.D.learn - function overload with mixin template bug?

reply Patric Dexheimer <patric.dexheimer gmail.com> writes:
1)

struct T{
     void f1(){writeln("default f1");}
     void f1(int x){writeln("overload f1");}
}
//main
T().f1();
T().f1(1);
//compiles and output as expected.


2)

mixin template add_function(){
     void f1(){writeln("default f1");}
}
struct T{
     mixin add_function;
     void f1(int x){writeln("overload f1");}
}
//main
T().f1();
T().f1(1);
//Error: function f355.T.f1 (int x) is not callable using 
argument types ()
/* What? i´m missing something here? */


3)

mixin template add_function(){
     void f1(){writeln("default f1");}
}
struct T{
     mixin add_function;
}
//main
T().f1();
//compiles and output as expected.


Function overloads coming from mixin templates are not being 
detected ?
May 17 2017
parent reply Adam D. Ruppe <destructionator gmail.com> writes:
On Wednesday, 17 May 2017 at 13:13:06 UTC, Patric Dexheimer wrote:

 Function overloads coming from mixin templates are not being 
 detected ?


A name being present in the struct means that name is NOT pulled 
from the mixin template. This is a feature, not a bug. It allows 
overriding of mixin template individual behavior. see: 
http://arsdnet.net/this-week-in-d/sep-27.html


To bring in the mixin overloads in addition to your current ones 
instead of overriding, use alias:

mixin Foo some_name;
alias foo = some_name.foo;
void foo() {} // now they are all combined
May 17 2017
parent Patric Dexheimer <patric.dexheimer gmail.com> writes:
On Wednesday, 17 May 2017 at 13:26:36 UTC, Adam D. Ruppe wrote:

 On Wednesday, 17 May 2017 at 13:13:06 UTC, Patric Dexheimer 
 wrote:

 Function overloads coming from mixin templates are not being 
 detected ?


 A name being present in the struct means that name is NOT 
 pulled from the mixin template. This is a feature, not a bug. 
 It allows overriding of mixin template individual behavior. 
 see: http://arsdnet.net/this-week-in-d/sep-27.html


 To bring in the mixin overloads in addition to your current 
 ones instead of overriding, use alias:

 mixin Foo some_name;
 alias foo = some_name.foo;
 void foo() {} // now they are all combined


Oh, thank you, didn´t know about it.
didn´t know about this syntax also "mixin Foo some_name;"
May 17 2017