lgoettgens/OddEvenIntegers.jl

Odd and even integers in Julia

OddEvenIntegers

This package provides the types Odd and Even that may wrap an integer. Using these types, the result of isodd and iseven may be evaluated at compile time.

julia> Odd(3)
3

julia> Even(4)
4

julia> @code_typed isodd(Odd(3))
CodeInfo(
1 ─     return true
) => Bool

julia> @code_typed iseven(Even(4))
CodeInfo(
1 ─     return true
) => Bool

This package interfaces with HalfIntegers, so that the half of an Odd or an Even may access the half-integer methods, some of which may be evaluated at compile time. The canonical way to construct and use such a type is:

julia> using OddEvenIntegers, HalfIntegers

julia> x = half(Odd(3))
3/2

julia> @code_typed isinteger(x)
CodeInfo(
1 ─     return false
) => Bool

julia> x + 1
5/2

julia> @code_typed isinteger(x + 1)
CodeInfo(
1 ─     return false
) => Bool