Merge pull request #638 from Kolaru/compat_rootfinding

Small fixes for ExactReal

ext/IntervalArithmeticForwardDiffExt.jl

@@ -48,4 +48,12 @@ function Base.:(^)(x::Interval, y::Dual{Ty, <:Interval}) where Ty
     return Dual{Ty}(expv, deriv * partials(y))
 end
 
+function Base.:(^)(x::Dual{<:Any, I}, y::ExactReal) where I<:Interval
+    return x^convert(I, y)
+end
+
+function Base.:(^)(x::ExactReal, y::Dual{<:Any, I}) where I<:Interval
+    return convert(I, x)^y
+end
+
 end

src/intervals/exact_literals.jl

@@ -54,6 +54,7 @@ struct ExactReal{T<:Real} <: Real
 end
 
 _value(x::ExactReal) = x.value # hook for interval constructor
+Base.to_index(i::ExactReal{<:Integer}) = i.value  # allow to index with ExactReal
 
 # conversion and promotion