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Scala Type Level Programming: The Natural Numbers: First Definitions
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sealed trait Nat { | |
type inc <: Nat | |
type dbl <: Nat | |
} | |
sealed trait MsbZero extends Nat { | |
override type inc = MsbOne | |
override type dbl = MsbZero | |
} | |
sealed trait MsbOne extends Nat { | |
override type inc = B0[MsbOne] | |
override type dbl = B0[MsbOne] | |
} | |
sealed trait B0[HigherBits <: Nat] extends Nat { | |
override type inc = B1[HigherBits] | |
override type dbl = B0[B0[HigherBits]] | |
} | |
sealed trait B1[HigherBits <: Nat] extends Nat { | |
override type inc = B0[HigherBits#inc] | |
override type dbl = B0[B1[HigherBits]] | |
} |
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