Q_SIGNAL_IMPL_D

Undocumented in source but is binding to C++. You might be able to learn more by searching the web for its name.
extern (C++)
enum Q_SIGNAL_IMPL_D = q{ struct Dummy{} import std.traits; void*[std.traits.Parameters!(__traits(parent, Dummy)).length + 1] _a = mixin((){ string r = "[null"; static foreach(i; 0..std.traits.Parameters!(__traits(parent, Dummy)).length) r ~= " , cast(void*)&" ~ std.traits.ParameterIdentifierTuple!(__traits(parent, Dummy))[i]; r ~= "]"; return r; }()); imported!q{qt.core.objectdefs}.QMetaObject.activate(this, &staticMetaObject, imported!q{qt.core.objectdefs}.MetaObjectImpl!(typeof(this)).signalIndex!(__traits(parent, Dummy)), _a.ptr); };

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