[Issue 20080] [2.087.0] Function overloads defined in mixin not callable

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=20080

Simen Kjaeraas <simen.kjaras at gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |simen.kjaras at gmail.com
         Resolution|---                         |DUPLICATE

--- Comment #1 from Simen Kjaeraas <simen.kjaras at gmail.com> ---
This is by design, and can easily be fixed with an alias:

mixin template Thing( )
{
    public void writeAThing( float val )
    {
        import std.stdio : writeln;

        writeln( val );
    }
}

struct ProperThing
{
    public void writeAThing( int val )
    {
        import std.stdio : writeln;

        writeln( val );
    }

    // Note that we must give the mixin a name:
    mixin Thing!() f;
    // Then this line adds it to the overload set:
    alias f.writeAThing writeAThing;
}

void main
{
    ProperThing thing;
    thing.writeAThing( 42.0f );
}


It's even possible to automate this with reflection:

string aliasAll(alias sym)()
{
    enum symName = __traits(identifier, sym);
    string result = "";

    foreach (e; __traits(allMembers, sym))
        result ~= "alias "~symName~"."~e~" "~e~";";

    return result;
}

And you'd use it like this:

    mixin Thing!() f;
    mixin(aliasAll!f);

*** This issue has been marked as a duplicate of issue 2157 ***

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