How are rational numbers implemented in Julia

Question

Are the numerator and denominator stored as integers? Specifically, how are implemented the basic operations: sum, subtraction, multiplication, division?

Answer 1

https://github.com/JuliaLang/julia/blob/248bbf6d61b643d0101bf96093cd7621e5bcf477/base/rational.jl#L9-L15

the code is fairly readable, in short:

struct Rational{T<:Integer} <: Real

means that both numerator and denominator have the same type, and that type is <: Integer.

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if you want to know how some operations are implemented, try running this in your REPL:

julia> @edit 1//2 + 3//4

it should bring you to https://github.com/JuliaLang/julia/blob/248bbf6d61b643d0101bf96093cd7621e5bcf477/base/rational.jl#L285

Answer 2

Even a faster and easier way to understand what is going on in Julia is just to use the dump command such as:

julia> dump(3//4)
Rational{Int64}
  num: Int64 3
  den: Int64 4