From 6fddd3e39efba19c68f08adabcff81cf38787693 Mon Sep 17 00:00:00 2001
From: Mark Spanbroek <mark@spanbroek.net>
Date: Mon, 13 Nov 2023 11:57:55 +0100
Subject: [PATCH] Move compress() into its own module

---
 poseidon2.nim          | 10 ++--------
 poseidon2/compress.nim | 10 ++++++++++
 2 files changed, 12 insertions(+), 8 deletions(-)
 create mode 100644 poseidon2/compress.nim

diff --git a/poseidon2.nim b/poseidon2.nim
index 91342fd..bdee038 100644
--- a/poseidon2.nim
+++ b/poseidon2.nim
@@ -5,22 +5,16 @@ import poseidon2/types
 import poseidon2/permutation
 import poseidon2/io
 import poseidon2/sponge
+import poseidon2/compress
 
 export sponge
+export compress
 export toBytes
 export elements
 export types
 
 #-------------------------------------------------------------------------------
 
-# 2-to-1 compression
-func compress*(a, b : F) : F =
-  var x = a
-  var y = b
-  var z : F ; setZero(z)
-  permInplace(x, y, z)
-  return x
-
 func merkleRoot*(xs: openArray[F]) : F =
   let a = low(xs)
   let b = high(xs)
diff --git a/poseidon2/compress.nim b/poseidon2/compress.nim
new file mode 100644
index 0000000..b0ce10e
--- /dev/null
+++ b/poseidon2/compress.nim
@@ -0,0 +1,10 @@
+import ./types
+import ./permutation
+
+# 2-to-1 compression
+func compress*(a, b : F) : F =
+  var x = a
+  var y = b
+  var z : F = zero
+  permInplace(x, y, z)
+  return x