macros for errors

core/electrum_client/src/types.rs

@@ -176,26 +176,17 @@ pub enum Error {
     SslHandshakeError(openssl::ssl::HandshakeError<std::net::TcpStream>),
 }
 
-impl std::convert::From<std::io::Error> for Error {
-    fn from(err: std::io::Error) -> Self {
-        Error::IOError(err)
-    }
-}
-
-impl std::convert::From<serde_json::error::Error> for Error {
-    fn from(err: serde_json::error::Error) -> Self {
-        Error::JSON(err)
-    }
-}
-
-impl std::convert::From<bitcoin::hashes::hex::Error> for Error {
-    fn from(err: bitcoin::hashes::hex::Error) -> Self {
-        Error::Hex(err)
-    }
+macro_rules! impl_error {
+    ( $from:ty, $to:ident ) => {
+        impl std::convert::From<$from> for Error {
+            fn from(err: $from) -> Self {
+                Error::$to(err)
+            }
+        }
+    };
 }
 
-impl std::convert::From<bitcoin::consensus::encode::Error> for Error {
-    fn from(err: bitcoin::consensus::encode::Error) -> Self {
-        Error::Bitcoin(err)
-    }
-}
+impl_error!(std::io::Error, IOError);
+impl_error!(serde_json::Error, JSON);
+impl_error!(bitcoin::hashes::hex::Error, Hex);
+impl_error!(bitcoin::consensus::encode::Error, Bitcoin);