Use Address type in RPC call signature

ethers/providers/jsonrpc.nim

@@ -28,8 +28,4 @@ proc new*(_: type JsonRpcProvider, url=defaultUrl): JsonRpcProvider =
 
 proc listAccounts*(provider: JsonRpcProvider): Future[seq[Address]] {.async.} =
   let client = await provider.client
-  var addresses: seq[Address]
-  for address in await client.eth_accounts():
-    if address =? Address.init(address):
-      addresses.add(address)
-  return addresses
+  return await client.eth_accounts()

ethers/providers/rpccalls.nim

@@ -1,6 +1,7 @@
 import std/os
 import pkg/json_rpc/rpcclient
 import ../basics
+import ./rpccalls/conversions
 
 const file = currentSourcePath.parentDir / "rpccalls" / "signatures.nim"
 

ethers/providers/rpccalls/conversions.nim

@@ -0,0 +1,11 @@
+import std/json
+import ../../basics
+
+func `%`*(address: Address): JsonNode =
+  %($address)
+
+func fromJson*(json: JsonNode, argname: string, result: var Address) =
+  if address =? Address.init(json.getStr()):
+    result = address
+  else:
+    raise newException(ValueError, "\""  & argname & "\"is not an Address")

ethers/providers/rpccalls/signatures.nim

@@ -1 +1 @@
-proc eth_accounts: seq[string]
+proc eth_accounts: seq[Address]