self->#x:binding-provides ->out = self->#x:binding-requires ->out;
self->#x:binding-requires ->in = self->#x:binding-provides ->in;
self->#x:binding-provides ->meta.requires = self->#x:binding-requires ->meta.requires;
self->#x:binding-requires ->meta.provides = self->#x:binding-provides ->meta.provides;
