Define dataids for BlockArray (#65)

Author: tkf

src/BlockArrays.jl

@@ -23,6 +23,7 @@ import Base: @propagate_inbounds, Array, to_indices, to_index,
             RangeIndex, Int, Integer, Number,
             +, -, min, max, *, isless, in, copy, copyto!, axes, @deprecate,
             BroadcastStyle
+using Base: dataids
 
 
 

src/blockarray.jl

@@ -276,6 +276,10 @@ end
     getblock(block_array, block_index.I...)[block_index.α...] = v
 end
 
+Base.dataids(arr::BlockArray) = (dataids(arr.blocks)..., dataids(arr.block_sizes)...)
+# This is not entirely valid.  In principle, we have to concatenate
+# all dataids of all blocks.  However, it makes `dataids` non-inferable.
+
 ########
 # Misc #
 ########

src/blocksizes.jl

@@ -26,6 +26,11 @@ BlockSizes(sizes::Vararg{AbstractVector{Int}, N}) where {N} =
 
 Base.:(==)(a::BlockSizes, b::BlockSizes) = cumulsizes(a) == cumulsizes(b)
 
+Base.dataids(b::BlockSizes) = _splatmap(dataids, b.cumul_sizes)
+# _splatmap taken from Base:
+_splatmap(f, ::Tuple{}) = ()
+_splatmap(f, t::Tuple) = (f(t[1])..., _splatmap(f, tail(t))...)
+
 function _cumul_vec(v::AbstractVector{T}) where {T}
     v_cumul = similar(v, length(v) + 1)
     z = one(T)