Compute pubkey from privkey, instead of keeping together, initPrivateKey (#13)

* Compute pubkey from privkey, instead of keeping together

* Added initPrivateKey

src/datatypes.nim

@@ -17,7 +17,6 @@ type
 
   PrivateKey* = object
     Fraw_key: array[32, byte]
-    Fpublic_key: PublicKey   # This is exported publicly through public_key
 
 type
   Scalar256 = distinct array[32, byte]
@@ -53,7 +52,6 @@ template genAccessors(name: untyped, fieldType, objType: typedesc): untyped =
 
 genAccessors(raw_key, array[64, byte], PublicKey)
 genAccessors(raw_key, array[32, byte], PrivateKey)
-genAccessors(public_key, PublicKey, PrivateKey)
 
 
 ## If we hide the fields we need to provide a custom `==` proc

src/datatypes_interface.nim

@@ -30,9 +30,11 @@ else:
 # ################################
 # Initialization
 
+proc initPrivateKey*(data: array[32, byte]): PrivateKey {.noInit, inline.} =
+  result.raw_key = data
+
 proc initPrivateKey*(hexString: string): PrivateKey {.noInit.} =
   hexToByteArrayBE(hexString, result.raw_key)
-  result.public_key = private_key_to_public_key(result)
 
 proc initPublicKey*(hexString: string): PublicKey {.noInit.} =
   var b: array[65, byte]
@@ -60,6 +62,9 @@ proc verify_msg*(key: PublicKey, message: string, sig: Signature): bool {.inline
 # # ################################
 # # Private key interface
 
+proc public_key*(key: PrivateKey): PublicKey {.inline.} =
+  private_key_to_public_key(key)
+
 proc sign_msg*(key: PrivateKey, message: openarray[byte]): Signature {.inline.} =
   let message_hash = keccak256.digest(message)
   ecdsa_sign(key, message_hash)

src/eth_keys.nim

@@ -8,11 +8,12 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import ./datatypes
-export PublicKey, PrivateKey, Signature, public_key, raw_key, `==`
 
 import ./datatypes_interface
 export datatypes_interface
 
+export PublicKey, PrivateKey, Signature, public_key, raw_key, `==`
+
 when defined(backend_native):
   import ttmath
   export ttmath