General Improvements to indexing (#137)

* Improved docs for indices
* consolidated the flatten_* code within to_indices
* removed superfluous keyword arguments from several functions
* Added support for IndexCartesian style to_index
* Multidim -> linear indexing

Author: Tokazama

Project.toml

@@ -1,6 +1,6 @@
 name = "ArrayInterface"
 uuid = "4fba245c-0d91-5ea0-9b3e-6abc04ee57a9"
-version = "3.1.6"
+version = "3.1.7"
 
 [deps]
 IfElse = "615f187c-cbe4-4ef1-ba3b-2fcf58d6d173"

src/ArrayInterface.jl

@@ -10,9 +10,15 @@ using Static: Zero, One, nstatic, _get_tuple, eq, ne, gt, ge, lt, le, eachop, ea
 using Base.Cartesian
 
 using Base: @propagate_inbounds, tail, OneTo, LogicalIndex, Slice, ReinterpretArray,
-    ReshapedArray
+    ReshapedArray, AbstractCartesianIndex
 
 
+## utilites for internal use only ##
+_int_or_static_int(::Nothing) = Int
+_int_or_static_int(x::Int) = StaticInt{x}
+_int(i::Integer) = Int(i)
+_int(i::StaticInt) = i
+
 @static if VERSION >= v"1.7.0-DEV.421"
     using Base: @aggressive_constprop
 else
@@ -21,6 +27,8 @@ else
     end
 end
 
+static_ndims(x) = static(ndims(x))
+
 if VERSION ≥ v"1.6.0-DEV.1581"
     _is_reshaped(::Type{ReinterpretArray{T,N,S,A,true}}) where {T,N,S,A} = true
     _is_reshaped(::Type{ReinterpretArray{T,N,S,A,false}}) where {T,N,S,A} = false
@@ -34,6 +42,8 @@ parameterless_type(x::Type) = __parameterless_type(x)
 
 const VecAdjTrans{T,V<:AbstractVector{T}} = Union{Transpose{T,V},Adjoint{T,V}}
 const MatAdjTrans{T,M<:AbstractMatrix{T}} = Union{Transpose{T,M},Adjoint{T,M}}
+const UpTri{T,M} = Union{UpperTriangular{T,M},UnitUpperTriangular{T,M}}
+const LoTri{T,M} = Union{LowerTriangular{T,M},UnitLowerTriangular{T,M}}
 
 @inline static_length(a::UnitRange{T}) where {T} = last(a) - first(a) + oneunit(T)
 @inline static_length(x) = Static.maybe_static(known_length, length, x)
@@ -57,12 +67,15 @@ parent_type(::Type{<:PermutedDimsArray{T,N,I1,I2,A}}) where {T,N,I1,I2,A} = A
 parent_type(::Type{Slice{T}}) where {T} = T
 parent_type(::Type{T}) where {T} = T
 parent_type(::Type{R}) where {S,T,A,N,R<:Base.ReinterpretArray{T,N,S,A}} = A
-
+parent_type(::Type{LoTri{T,M}}) where {T,M} = M
+parent_type(::Type{UpTri{T,M}}) where {T,M} = M
+parent_type(::Type{Diagonal{T,V}}) where {T,V} = V
 """
     has_parent(::Type{T}) -> StaticBool
 
 Returns `True` if `parent_type(T)` a type unique to `T`.
 """
+has_parent(x) = has_parent(typeof(x))
 has_parent(::Type{T}) where {T} = _has_parent(parent_type(T), T)
 _has_parent(::Type{T}, ::Type{T}) where {T} = False()
 _has_parent(::Type{T1}, ::Type{T2}) where {T1,T2} = True()
@@ -786,15 +799,6 @@ end
     end
 end
 
-include("ranges.jl")
-include("indexing.jl")
-include("dimensions.jl")
-include("axes.jl")
-include("size.jl")
-include("stridelayout.jl")
-include("broadcast.jl")
-
-
 abstract type AbstractArray2{T,N} <: AbstractArray{T,N} end
 
 Base.size(A::AbstractArray2) = map(Int, ArrayInterface.size(A))
@@ -836,6 +840,14 @@ end
     return setindex!(A, val; kwargs...)
 end
 
+include("ranges.jl")
+include("indexing.jl")
+include("dimensions.jl")
+include("axes.jl")
+include("size.jl")
+include("stridelayout.jl")
+include("broadcast.jl")
+
 function __init__()
 
     @require SuiteSparse = "4607b0f0-06f3-5cda-b6b1-a6196a1729e9" begin

src/axes.jl

@@ -57,9 +57,6 @@ function axes_types(::Type{T}) where {N,T<:Base.ReshapedArray{<:Any,N}}
     return Tuple{Vararg{OptionallyStaticUnitRange{One,Int},N}}
 end
 
-_int_or_static_int(::Nothing) = Int
-_int_or_static_int(x::Int) = StaticInt{x}
-
 @inline function axes_types(::Type{T}) where {N,P,I,T<:SubArray{<:Any,N,P,I}}
     return eachop_tuple(_sub_axis_type, to_parent_dims(T), T)
 end
@@ -126,6 +123,8 @@ similar_type(::Type{OptionallyStaticUnitRange{One,StaticInt{N1}}}, ::Type{Int},
 Return a valid range that maps to each index along dimension `d` of `A`.
 """
 axes(a, dim) = axes(a, to_dims(a, dim))
+axes(a, dims::Tuple) = (axes(a, first(dims)), axes(a, tail(dims))...)
+axes(a, ::Tuple{}) = ()
 function axes(a::A, dim::Integer) where {A}
     if parent_type(A) <: A
         return Base.axes(a, Int(dim))
@@ -157,4 +156,6 @@ end
 axes(A::SubArray) = Base.axes(A)  # TODO implement ArrayInterface version
 axes(A::ReinterpretArray) = Base.axes(A)  # TODO implement ArrayInterface version
 axes(A::Base.ReshapedArray) = Base.axes(A)  # TODO implement ArrayInterface version
+axes(A::CartesianIndices) = A.indices
+axes(A::LinearIndices) = A.indices