compat for JuliaLang/julia#12472

src/Compat.jl

@@ -543,4 +543,22 @@ if VERSION < v"0.4.0-dev+6506"
     export include_dependency
 end
 
+if VERSION < v"0.4.0-dev+6068"
+    Base.real{T<:Real}(::Type{T}) = T
+    Base.real{T<:Real}(::Type{Complex{T}}) = T
+end
+
+if VERSION < v"0.4.0-dev+6578"
+    rtoldefault{T<:AbstractFloat}(::Type{T}) = sqrt(eps(T))
+    rtoldefault{T<:Real}(::Type{T}) = 0
+    rtoldefault{T<:Number,S<:Number}(x::Union(T,Type{T}), y::Union(S,Type{S})) = rtoldefault(promote_type(real(T),real(S)))
+    function Base.isapprox{T<:Number,S<:Number}(x::AbstractArray{T}, y::AbstractArray{S}; rtol::Real=rtoldefault(T,S), atol::Real=0, norm::Function=vecnorm)
+        d = norm(x - y)
+        return isfinite(d) ? d <= atol + rtol*max(norm(x), norm(y)) : x == y
+    end
+    const ≈ = isapprox
+    ≉(x,y) = !(x ≈ y)
+    export ≈, ≉
+end
+
 end # module

test/runtests.jl

@@ -412,3 +412,10 @@ Compat.@irrational mathconst_one 1.0 big(1.)
 
 @test nothing === __precompile__(false) # tests should never be precompiled
 @test nothing === include_dependency("foo")
+
+@test real(Int) == real(Complex{Int}) == Int
+
+@test [1,2,3] ≈ [1,2,3+1e-9]
+@test [0,1] ≈ [1e-9, 1]
+@test [0,Inf] ≈ [0,Inf]
+@test [0,Inf] ≉ [0,-Inf]