protocol A1 {} protocol A2: A1 {} protocol A3: A2 {} struct C<R>: A1 extension C: A2, A3 where R == X extension C: A2 where R == Y (edited)protocol A1 {} protocol A2: A1 {} protocol A3: A2 {} struct C<R>: A1 extension C: A2, A3 where R == X extension C: A2 where R == Y (edited)Complex<R> にして、複素数体 C = Complex<Real> と ガウス整数環 Complex<Int> を共通化しようとしまして、 (edited)