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Scala Type Level Programming: The Natural Numbers: Exponentiation
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sealed trait Nat { | |
type exp[That <: Nat] <: Nat | |
type expflip[That <: Nat] <: Nat | |
} | |
sealed trait MsbZero extends Nat { | |
override type exp[That <: Nat] = MsbZero | |
override type expflip[That <: Nat] = MsbOne | |
} | |
sealed trait MsbOne extends Nat { | |
override type exp[That <: Nat] = MsbOne | |
override type expflip[That <: Nat] = That | |
} | |
sealed trait B0[HigherBits <: Nat] extends Nat { | |
override type exp[That <: Nat] = That#expflip[B0[HigherBits]] | |
override type expflip[That <: Nat] = HigherBits#expflip[That#mult[That]] | |
} | |
sealed trait B1[HigherBits <: Nat] extends Nat { | |
override type exp[That <: Nat] = That#expflip[B1[HigherBits]] | |
override type expflip[That <: Nat] = HigherBits#expflip[That#mult[That]]#mult[That] | |
} |
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