Support range(::ClosedInterval{<:Integer}) -> UnitRange

Also restricts `convert(::Type{<:AbstractUnitRange}, i)` to `i::ClosedInterval`. That definition wouldn't make sense for an open interval.

Author: timholy

src/IntervalSets.jl

@@ -5,7 +5,7 @@ module IntervalSets
 # package code goes here
 
 using Base: @pure
-import Base: eltype, convert, show, in, length, isempty, isequal, issubset, ==, hash, union, intersect, minimum, maximum
+import Base: eltype, convert, show, in, length, isempty, isequal, issubset, ==, hash, union, intersect, minimum, maximum, range
 
 using Compat
 
@@ -27,9 +27,6 @@ function convert{I<:AbstractInterval}(::Type{I}, r::Range)
     T = eltype(I)
     I(convert(T, minimum(r)), convert(T, maximum(r)))
 end
-function convert{R<:AbstractUnitRange,I<:Integer}(::Type{R}, i::AbstractInterval{I})
-    R(minimum(i), maximum(i))
-end
 
 ordered{T}(a::T, b::T) = ifelse(a < b, (a, b), (b, a))
 ordered(a, b) = ordered(promote(a, b)...)

src/closed.jl

@@ -76,3 +76,9 @@ function width{T}(A::ClosedInterval{T})
     _width = A.right - A.left
     max(zero(_width), _width)   # this works when T is a Date
 end
+
+function convert{R<:AbstractUnitRange,I<:Integer}(::Type{R}, i::ClosedInterval{I})
+    R(minimum(i), maximum(i))
+end
+
+range{I<:Integer}(i::ClosedInterval{I}) = convert(UnitRange{I}, i)

test/runtests.jl

@@ -11,6 +11,7 @@ using Base.Test
         I = 0..3
         @test string(I) == "0..3"
         @test convert(UnitRange, I) === 0:3
+        @test range(I) === 0:3
         @test convert(UnitRange{Int16}, I) === Int16(0):Int16(3)
         J = 3..2
         K = 5..4