From 6b862701da54c86e72e9c3664ae8063ea4792a8e Mon Sep 17 00:00:00 2001
From: mtfishman <mfishman@flatironinstitute.org>
Date: Thu, 17 Jul 2025 18:15:14 -0400
Subject: [PATCH] Introduce getunstoredindex_function

---
 Project.toml                        | 2 +-
 src/abstractsparsearrayinterface.jl | 9 +++++++--
 src/sparsearraydok.jl               | 3 ++-
 3 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/Project.toml b/Project.toml
index 7f585fd..b45de75 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "SparseArraysBase"
 uuid = "0d5efcca-f356-4864-8770-e1ed8d78f208"
 authors = ["ITensor developers <support@itensor.org> and contributors"]
-version = "0.5.11"
+version = "0.6.1"
 
 [deps]
 Accessors = "7d9f7c33-5ae7-4f3b-8dc6-eff91059b697"
diff --git a/src/abstractsparsearrayinterface.jl b/src/abstractsparsearrayinterface.jl
index 6af80e6..e7b9bca 100644
--- a/src/abstractsparsearrayinterface.jl
+++ b/src/abstractsparsearrayinterface.jl
@@ -4,7 +4,7 @@ using DerivableInterfaces:
 
 function eachstoredindex end
 function getstoredindex end
-function getunstoredindex end
+function getunstoredindex_function end
 function isstored end
 function setstoredindex! end
 function setunstoredindex! end
@@ -12,6 +12,11 @@ function storedlength end
 function storedpairs end
 function storedvalues end
 
+@inline function getunstoredindex(a::AbstractArray{<:Any,N}, I::Vararg{Int,N}) where {N}
+  @boundscheck checkbounds(a, I...)
+  return getunstoredindex_function(a)(a, I...)
+end
+
 # Replace the function for accessing
 # unstored values.
 function set_getunstoredindex end
@@ -90,7 +95,7 @@ end
   a::AbstractArray, T::Type, size::Tuple{Vararg{Int}}
 )
   # TODO: Define `default_similartype` or something like that?
-  return SparseArrayDOK{T}(undef, size)
+  return SparseArrayDOK{T}(undef, size; getunstored=getunstoredindex_function(a))
 end
 
 # map over a specified subset of indices of the inputs.
diff --git a/src/sparsearraydok.jl b/src/sparsearraydok.jl
index 8d123dc..78eac00 100644
--- a/src/sparsearraydok.jl
+++ b/src/sparsearraydok.jl
@@ -87,9 +87,10 @@ end
   @boundscheck checkbounds(a, I...)
   return storage(a)[CartesianIndex(I)]
 end
+@inline getunstoredindex_function(a::SparseArrayDOK) = a.getunstored
 @inline function getunstoredindex(a::SparseArrayDOK{<:Any,N}, I::Vararg{Int,N}) where {N}
   @boundscheck checkbounds(a, I...)
-  return a.getunstored(a, I...)
+  return getunstoredindex_function(a)(a, I...)
 end
 @inline function setstoredindex!(
   a::SparseArrayDOK{<:Any,N}, value, I::Vararg{Int,N}