From 1827d6a3c634f47b2a6835c29bcf554f7db28386 Mon Sep 17 00:00:00 2001
From: lkdvos <lukas.devos@ugent.be>
Date: Tue, 2 Jul 2024 07:33:28 +0200
Subject: [PATCH] Refactor _interleave

---
 src/auxiliary/auxiliary.jl | 10 ++++++++++
 src/tensors/tensor.jl      |  6 ------
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/auxiliary/auxiliary.jl b/src/auxiliary/auxiliary.jl
index e8c9445b..3cf0da46 100644
--- a/src/auxiliary/auxiliary.jl
+++ b/src/auxiliary/auxiliary.jl
@@ -49,3 +49,13 @@ end
 else
     using Base: @constprop
 end
+
+"""
+    _interleave(a::NTuple{N}, b::NTuple{N}) -> NTuple{2N}
+
+Interleave two tuples of the same length.
+"""
+_interleave(::Tuple{}, ::Tuple{}) = ()
+function _interleave(a::NTuple{N}, b::NTuple{N}) where {N}
+    return (a[1], b[1], _interleave(tail(a), tail(b))...)
+end
diff --git a/src/tensors/tensor.jl b/src/tensors/tensor.jl
index 64c20e7d..cf4f3d7b 100644
--- a/src/tensors/tensor.jl
+++ b/src/tensors/tensor.jl
@@ -395,12 +395,6 @@ function TensorMap(data::DenseArray, codom::ProductSpace{S,N₁}, dom::ProductSp
     return t
 end
 
-function _interleave(a::Base.Dims{N}, b::Base.Dims{N}) where {N}
-    return ntuple(2N) do i
-        halfi, rem = divrem(i, 2)
-        return getindex(rem == 1 ? a : b, halfi + rem)
-    end
-end
 # Efficient copy constructors
 #-----------------------------
 Base.copy(t::TrivialTensorMap) = typeof(t)(copy(t.data), t.codom, t.dom)