Add: julia-0.6.2

Former-commit-id: ccc667cf67d569f3fb3df39aa57c2134755a7551

julia-0.6.2/share/julia/base/traits.jl

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+# This file is a part of Julia. License is MIT: https://julialang.org/license
+
+## numeric/object traits
+# trait for objects that have an ordering
+abstract type TypeOrder end
+struct HasOrder <: TypeOrder end
+struct Unordered <: TypeOrder end
+
+TypeOrder(instance) = TypeOrder(typeof(instance))
+TypeOrder(::Type{<:Real}) = HasOrder()
+TypeOrder(::Type{<:Any}) = Unordered()
+
+# trait for objects that support arithmetic
+abstract type TypeArithmetic end
+struct ArithmeticRounds <: TypeArithmetic end     # least significant bits can be lost
+struct ArithmeticOverflows <: TypeArithmetic end  #  most significant bits can be lost
+struct ArithmeticUnknown <: TypeArithmetic end
+
+TypeArithmetic(instance) = TypeArithmetic(typeof(instance))
+TypeArithmetic(::Type{<:AbstractFloat}) = ArithmeticRounds()
+TypeArithmetic(::Type{<:Integer}) = ArithmeticOverflows()
+TypeArithmetic(::Type{<:Any}) = ArithmeticUnknown()