minor improvements

poseidon2.nim

@@ -36,8 +36,8 @@ func spongeWithRate1*(xs: openArray[F]) : F =
   var s1 : F = zero
   var s2 : F = zero
 
-  for i in 0..<n:
-    s0 += xs[a+i]
+  for x in xs:
+    s0 += x
     permInplace(s0,s1,s2)
 
   # padding

poseidon2/roundfun.nim

@@ -7,9 +7,6 @@ import ./roundconst
 
 #-------------------------------------------------------------------------------
 
-const zero* : F = getZero()
-const one*  : F = getOne()
-
 const externalRoundConst : array[24, F] = arrayFromHex( externalRoundConstStr )
 const internalRoundConst : array[56, F] = arrayFromHex( internalRoundConstStr )
 

poseidon2/types.nim

@@ -18,19 +18,19 @@ func getZero*() : F =
   setZero(z)
   return z
 
-func getOne*() : F = 
-  var y : F
-  # y.fromUint(1'u32)       # WTF, why does this not compile ???
-  y.fromHex("0x01")
-  return y
-
-# for some reason this one does not compile... ???
-# (when actually called)
+# Remark: since `fromInt()` does not work at compile time, this doesn't either
 func toF*(a: int) : F =
   var y : F
   y.fromInt(a)
   return y
 
+#-------------------------------------------------------------------------------
+
+const zero* : F = getZero()
+const one*  : F = fromHex(F,"0x01")     # note: `fromUint()` does not work at compile time
+
+#-------------------------------------------------------------------------------
+
 func hexToF*(s : string, endian: static Endianness = bigEndian) : F =
   let bigint = B.fromHex(s, endian)
   return F.fromBig(bigint)

tests/poseidon2/testPoseidon2.nim

@@ -59,7 +59,6 @@ suite "poseidon2":
       for i in 1..n:
         xs.add( toF(i) )
       let h = spongeWithRate1(xs)
-      # echo(toDecimal(h))
       check toDecimal(h) == expectedSpongeResultsRate1[n] 
 
   test "sponge with rate=2":
@@ -68,7 +67,6 @@ suite "poseidon2":
       for i in 1..n:
         xs.add( toF(i) )
       let h = spongeWithRate2(xs)
-      # echo(toDecimal(h))
       check toDecimal(h) == expectedSpongeResultsRate2[n] 
 
   test "merkle root of field elements":