Add array[N, byte].fromHex(string)

stew/byteutils.nim

@@ -83,6 +83,11 @@ func hexToByteArray*[N: static[int]](hexStr: string): array[N, byte]
   ## Read an hex string and store it in a byte array. No "endianness" reordering is done.
   hexToByteArray(hexStr, result)
 
+func fromHex*[N](A: type array[N, byte], hexStr: string): A
+                {.raises: [ValueError, Defect], noInit, inline.}=
+  ## Read an hex string and store it in a byte array. No "endianness" reordering is done.
+  hexToByteArray(hexStr, result)
+
 func hexToPaddedByteArray*[N: static[int]](hexStr: string): array[N, byte]
                                           {.raises: [ValueError, Defect].} =
   ## Read a hex string and store it in a byte array `output`.

tests/test_byteutils.nim

@@ -36,6 +36,18 @@ suite "Byte utils":
     expect(ValueError): discard hexToByteArray[1]("")
     expect(ValueError): discard hexToByteArray[1]("1")
 
+  test "array.fromHex":
+    let
+      s = "0x12345678"
+      a2 = array[2, byte].fromHex(s)
+      a4 = array[4, byte].fromHex(s)
+
+    check:
+      a2.toHex == "1234"
+      a4.toHex == "12345678"
+
+    expect(ValueError): echo array[5, byte].fromHex(s)
+
   test "toHex":
     check simpleBArray.toHex == "12345678"
     check hexToSeqByte("12345678") == simpleBArray