Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/prelude/Complex/Read_Complex.hs
module Complex(Read(..)) where import DComplex instance (Read a, RealFloat a) => Read (Complex a) where readsPrec p = readParen (p >= 6) (\r -> [(x :+ y,v) | (x,v) <- readsPrec 6 r, (":+",u) <- lex v, (y,w) <- readsPrec 6 u])