From bca616b5ddaed96d1b3354620594fcced5250549 Mon Sep 17 00:00:00 2001
From: David-Mao <david.my29@gmail.com>
Date: Wed, 5 Jul 2023 19:04:11 -0400
Subject: [PATCH] slices: change implementation for Clone()
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Change the implementation of slices Clone. It's 28% faster on my laptop. As discussed in https://github.com/golang/go/issues/57433#issuecomment-1403961661, no extra issue is needed for this simple fix.

goos: darwin
goarch: arm64
pkg: github.com/David-Mao/Euclid/Go/utils
         │   old.txt   │               new.txt               │
         │   sec/op    │   sec/op     vs base                │
Clone-12   16.95n ± 1%   12.06n ± 2%  -28.85% (p=0.000 n=10)
---
 src/slices/slices.go | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/slices/slices.go b/src/slices/slices.go
index afeed0afb522ce..9c87365071ddb2 100644
--- a/src/slices/slices.go
+++ b/src/slices/slices.go
@@ -340,7 +340,9 @@ func Clone[S ~[]E, E any](s S) S {
 	if s == nil {
 		return nil
 	}
-	return append(S([]E{}), s...)
+	t := make([]E, len(s))
+	copy(t, s)
+	return t
 }
 
 // Compact replaces consecutive runs of equal elements with a single copy.