AxisArrays features: support eltype, convert, minimum, maximum, etc

Author: timholy

src/IntervalSets.jl

@@ -4,12 +4,24 @@ module IntervalSets
 
 # package code goes here
 
-import Base: show, in, length, isempty, isequal, issubset, ==, union, intersect
+using Base: @pure
+import Base: eltype, convert, show, in, length, isempty, isequal, issubset, ==, hash, union, intersect, minimum, maximum
 
-export ClosedInterval, ⊇, .., ±, ordered
+export AbstractInterval, ClosedInterval, ⊇, .., ±, ordered
+
+abstract AbstractInterval{T}
 
 include("closed.jl")
 
+eltype{T}(::Type{AbstractInterval{T}}) = T
+@pure eltype{I<:AbstractInterval}(::Type{I}) = eltype(supertype(I))
+
+convert{I<:AbstractInterval}(::Type{I}, i::I) = i
+function convert{I<:AbstractInterval}(::Type{I}, i::AbstractInterval)
+    T = eltype(I)
+    I(convert(T, i.left), convert(T, i.right))
+end
+
 ordered{T}(a::T, b::T) = ifelse(a < b, (a, b), (b, a))
 ordered(a, b) = ordered(promote(a, b)...)
 

src/closed.jl

@@ -1,8 +1,8 @@
 """
-A `ClosedInterval(left, right)` is an interval set that includes both its upper and lower bounds. In 
+A `ClosedInterval(left, right)` is an interval set that includes both its upper and lower bounds. In
 mathematical notation, the constructed range is `[left, right]`.
 """
-immutable ClosedInterval{T}
+immutable ClosedInterval{T} <: AbstractInterval{T}
     left::T
     right::T
 
@@ -20,6 +20,9 @@ function ClosedInterval(left, right)
     ClosedInterval{T}(checked_conversion(T, left, right)...)
 end
 
+ClosedInterval(i::AbstractInterval) = convert(ClosedInterval{eltype(i)}, i)
+(::Type{ClosedInterval{T}}){T}(i::AbstractInterval) = convert(ClosedInterval{T}, i)
+
 ..(x, y) = ClosedInterval(x, y)
 
 ±(x, y) = ClosedInterval(x - y, x + y)
@@ -28,13 +31,21 @@ end
 show(io::IO, I::ClosedInterval) = print(io, I.left, "..", I.right)
 
 in(v, I::ClosedInterval) = I.left <= v <= I.right
+in(a::ClosedInterval, b::ClosedInterval) = (b.left <= a.left) & (a.right <= b.right)
 
 isempty(A::ClosedInterval) = A.left > A.right
 
 isequal(A::ClosedInterval, B::ClosedInterval) = (isequal(A.left, B.left) & isequal(A.right, B.right)) | (isempty(A) & isempty(B))
 
 ==(A::ClosedInterval, B::ClosedInterval) = (A.left == B.left && A.right == B.right) || (isempty(A) && isempty(B))
 
+const _closed_interval_hash = UInt == UInt64 ? 0x1588c274e0a33ad4 : 0x1e3f7252
+
+hash(I::ClosedInterval, h::UInt) = hash(I.left, hash(I.right, hash(_closed_interval_hash, h)))
+
+minimum(I::ClosedInterval) = I.left
+maximum(I::ClosedInterval) = I.right
+
 function intersect(A::ClosedInterval, B::ClosedInterval)
     left = max(A.left, B.left)
     right = min(A.right, B.right)

test/runtests.jl

@@ -11,18 +11,25 @@ using Base.Test
         @test_throws ArgumentError :a .. "b"
         I = 0..3
         print(io, I)
-        @test String(io) == "0..3"
+        @test takebuf_string(io) == "0..3"
         J = 3..2
         K = 5..4
         L = 3 ± 2
         M = ClosedInterval(2, 5.0)
-        takebuf_array(io)
         print(io, M)
-        @test String(io) == "2.0..5.0"
+        @test takebuf_string(io) == "2.0..5.0"
         N = ClosedInterval(UInt8(255), 300)
         O = CartesianIndex(1, 2, 3, 4) ± 2
         @test O == (-1..3, 0..4, 1..5, 2..6)
 
+        @test eltype(I) == Int
+        @test eltype(M) == Float64
+        @test convert(ClosedInterval{Float64}, I) === 0.0..3.0
+        @test !(convert(ClosedInterval{Float64}, I) === 0..3)
+        @test ClosedInterval{Float64}(1,3) === 1.0..3.0
+        @test ClosedInterval(0.5..2.5) === 0.5..2.5
+        @test ClosedInterval{Int}(1.0..3.0) === 1..3
+
         @test !isempty(I)
         @test isempty(J)
         @test J == K
@@ -34,9 +41,13 @@ using Base.Test
         @test isequal(J, K)
 
         @test typeof(M.left) == typeof(M.right) && typeof(M.left) == Float64
-        @test typeof(N.left) == typeof(N.right) && typeof(N.left) == Int 
+        @test typeof(N.left) == typeof(N.right) && typeof(N.left) == Int
+
+        @test maximum(I) === 3
+        @test minimum(I) === 0
 
         @test 2 in I
+        @test 1..2 in 0.5..2.5
 
         @test I ∪ L == ClosedInterval(0, 5)
         @test I ∩ L == ClosedInterval(1, 3)
@@ -60,5 +71,7 @@ using Base.Test
         @test (ClosedInterval(7, 9) ⊆ I) == false
         @test I ⊇ I
         @test I ⊇ ClosedInterval(1, 2)
+
+        @test hash(1..3) == hash(1.0..3.0)
     end
 end