Result wrapper is optional.

Fixes #49.

Author: Yamakaky

CHANGELOG.md

@@ -10,6 +10,7 @@
 - Error is now a struct.
 - The declarations order is more flexible.
 - Way better error reporting when there is a syntax error in the macro call.
+- `Result` generation can be disabled.
 
 # 0.5.0
 

src/error_chain.rs

@@ -17,6 +17,21 @@ macro_rules! error_chain_processed {
         types {
             $error_name:ident, $error_kind_name:ident, $result_name:ident;
         }
+        $( $rest: tt )*
+    ) => {
+        error_chain_processed! {
+            types {
+                $error_name, $error_kind_name;
+            }
+            $( $rest )*
+        }
+        /// Convenient wrapper around `std::Result`.
+        pub type $result_name<T> = ::std::result::Result<T, $error_name>;
+    };
+    (
+        types {
+            $error_name:ident, $error_kind_name:ident;
+        }
 
         links {
             $( $link_error_path:path, $link_variant:ident $(, #[$meta_links:meta])*; ) *
@@ -204,9 +219,6 @@ macro_rules! error_chain_processed {
                 e.kind
             }
         }
-
-        /// Convenient wrapper around `std::Result`.
-        pub type $result_name<T> = ::std::result::Result<T, $error_name>;
     };
 }
 

src/lib.rs

@@ -127,6 +127,12 @@
 //!         Error, ErrorKind, Result;
 //!     }
 //!
+//!     // Without the `Result` wrapper:
+//!     //
+//!     // types {
+//!     //     Error, ErrorKind;
+//!     // }
+//!
 //!     // Automatic conversions between this error chain and other
 //!     // error chains. In this case, it will e.g. generate an
 //!     // `ErrorKind` variant called `Dist` which in turn contains

tests/tests.rs

@@ -389,3 +389,23 @@ mod attributes_test {
         }
     }
 }
+
+#[test]
+fn with_result() {
+    error_chain! {
+        types {
+            Error, ErrorKind, Result;
+        }
+    }
+    let _: Result<()> = Ok(());
+}
+
+#[test]
+fn without_result() {
+    error_chain! {
+        types {
+            Error, ErrorKind;
+        }
+    }
+    let _: Result<(), ()> = Ok(());
+}