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Author: kshyatt

src/tensors/tensoroperations.jl

@@ -19,11 +19,7 @@ end
 # seems necessary for GPU-backed BlockTensorMaps but
 # maybe not the most efficient approach?
 function TO.tensorscalar(t::AbstractBlockTensorMap{T, S, 0, 0}) where {T, S}
-    Bs = TK.blocks(t)
-    B_ends = collect.(map(b -> collect.(getfield(b, :blocks)), map(last, Bs)))
-    inds = findall(!iszero ∘ last, B_ends)
-    isempty(inds) && return zero(TKscalartype(t))
-    return only(last(B_ends[only(inds)]))
+    return prod(TO.tensorscalar, nonzero_values(t))
 end
 
 # tensoralloc_contract