add support for Dates

src/indexing.jl

@@ -199,7 +199,11 @@ axisindexes{T}(::Type{Dimensional}, ax::AbstractVector{T}, idx::ClosedInterval)
 # (the fencepost problem). As such, we need to be careful about how and when we
 # snap the provided intervals and offsets to exact axis values (and indices).
 # 
-# 
+# Note that this is fundamentally different than indexing by a single interval;
+# whereas those intervals are specified in the same units as the elements of the
+# axis itself, repeated intervals are specified in terms of _offsets_. This is
+# most obvious with dates; single intervals are between dates, repeated
+# intervals use intervals of days (for example) and offsets of dates.
 axisindexes(::Type{Dimensional}, ax::AbstractVector, idx::RepeatedInterval) = error("repeated intervals might select a varying number of elements for non-range axes; use a repeated Range of indices instead")
 function axisindexes(::Type{Dimensional}, ax::Range, idx::RepeatedInterval)
     idxs, vals = relativewindow(ax, idx.window)

src/search.jl

@@ -25,12 +25,16 @@ function unsafe_searchsortednearest(vec::Range, x)
 end
 
 
-nsteps(x, step) = floor(Int, abs(x / step)) * Int(sign(x))
+function nsteps(x, step)
+    offset = floor(Int, abs(x / step))
+    return x < zero(x) ? -offset : offset
+end
 function nsteps{T}(x, step::Base.TwicePrecision{T})
     # this is basically a hack because Base hasn't defined x/step at TwicePrecision resolution
     nf = abs(x / convert(T, step))
     nc = ceil(Int, nf)
-    return (abs(convert(T, nc*step)) <= abs(x) ? nc : floor(Int, nf)) * Int(sign(x))
+    offset = (abs(convert(T, nc*step)) <= abs(x) ? nc : floor(Int, nf))
+    return x < zero(x) ? -offset : offset
 end
 
 _step(r::Range) = step(r)

test/indexing.jl

@@ -121,7 +121,6 @@ Base.div(x::IntLike, y::IntLike) = div(x.val, y.val)
 Base.:*(x::IntLike, y::Int) = IntLike(x.val * y)
 Base.:*(x::Int, y::IntLike) = y*x
 Base.:/(x::IntLike, y::Int) = IntLike(x.val / y)
-Base.abs(x::IntLike) = IntLike(abs(x.val))
 Base.promote_rule(::Type{IntLike}, ::Type{Int}) = Int
 Base.convert(::Type{Int}, x::IntLike) = x.val
 using AxisArrays
@@ -180,3 +179,11 @@ A = AxisArray(rand(2,2), :x, :y)
 acc = zeros(Int, 4, 1, 2)
 Base.mapreducedim!(x->x>5, +, acc, A3)
 @test acc == reshape([1 3; 2 3; 2 3; 2 3], 4, 1, 2)
+
+# Test using dates
+using Base.Dates: Day, Month
+A = AxisArray(1:365, Date(2017,1,1):Date(2017,12,31))
+@test A[Date(2017,2,1) .. Date(2017,2,28)] == collect(31 + (1:28)) # February
+@test A[(-Day(13)..Day(14)) + Date(2017,2,14)] == collect(31 + (1:28))
+@test A[(-Day(14)..Day(14)) + DateTime(2017,2,14,12)] == collect(31 + (1:28))
+@test A[(Day(0)..Day(6)) + (Date(2017,1,1):Month(1):Date(2017,4,12))] == [1:7 32:38 60:66 91:97]