Variant(Error) in links and foreign_links.

It uniforms the syntax with `errors`.

Author: Yamakaky

CHANGELOG.md

@@ -1,3 +1,7 @@
+# Unreleased
+
+- New `Variant(Error) #[attrs]` for `links` and `foreign_links`.
+
 # 0.6.0
 
 - Conditional compilation for error variants.

examples/all.rs

@@ -22,14 +22,14 @@ error_chain! {
 
     // Automatic bindings to others error types generated by `error_chain!`.
     links {
-        inner::Error, Inner;
+        Inner(inner::Error);
         // Attributes can be added at the end of the declaration.
-        feature::Error, Feature, #[cfg(feature = "a_feature")];
+        Feature(feature::Error) #[cfg(feature = "a_feature")];
     }
 
     // Bindings to types implementing std::error::Error.
     foreign_links {
-        ::std::io::Error, Io;
+        Io(::std::io::Error);
     }
 }
 

examples/doc.rs

@@ -13,10 +13,10 @@ pub mod inner {
 
 error_chain! {
     links {
-        inner::Error, Test, #[doc = "Doc"];
+        Inner(inner::Error) #[doc = "Doc"];
     }
     foreign_links {
-        ::std::io::Error, Io, #[doc = "Io"];
+        Io(::std::io::Error) #[doc = "Io"];
     }
     errors {
         /// Doc

src/error_chain.rs

@@ -13,6 +13,7 @@ macro_rules! error_chain_processed {
             $( $rest )*
         }
     };
+    // With `Result` wrapper.
     (
         types {
             $error_name:ident, $error_kind_name:ident, $result_name:ident;
@@ -28,17 +29,20 @@ macro_rules! error_chain_processed {
         /// Convenient wrapper around `std::Result`.
         pub type $result_name<T> = ::std::result::Result<T, $error_name>;
     };
+    // Without `Result` wrapper.
     (
         types {
             $error_name:ident, $error_kind_name:ident;
         }
 
         links {
-            $( $link_error_path:path, $link_variant:ident $(, #[$meta_links:meta])*; ) *
+            $( $link_variant:ident ( $link_error_path:path )
+               $( #[$meta_links:meta] )*; ) *
         }
 
         foreign_links {
-            $( $foreign_link_error_path:path, $foreign_link_variant:ident $(, #[$meta_foreign_links:meta])*; )*
+            $( $foreign_link_variant:ident ( $foreign_link_error_path:path )
+               $( #[$meta_foreign_links:meta] )*; )*
         }
 
         errors {

src/lib.rs

@@ -117,7 +117,12 @@
 //! Assuming you are using crate-level error types, typically you will
 //! define an `errors` module and inside it call `error_chain!`:
 //!
-//! ```ignore
+//! ```
+//! # #[macro_use] extern crate error_chain;
+//! mod other_error {
+//!     error_chain! {}
+//! }
+//!
 //! error_chain! {
 //!     // The type defined for this error. These are the conventional
 //!     // and recommended names, but they can be arbitrarily chosen.
@@ -143,8 +148,7 @@
 //!     //
 //!     // This section can be empty.
 //!     links {
-//!         ::rustup_dist::Error, Dist;
-//!         ::rustup_utils::Error, Utils, #[cfg(unix)];
+//!         Another(other_error::Error) #[cfg(unix)];
 //!     }
 //!
 //!     // Automatic conversions between this error chain and other
@@ -157,8 +161,8 @@
 //!     //
 //!     // This section can be empty.
 //!     foreign_links {
-//!         ::temp::Error, Temp;
-//!         io::Error, Io, #[cfg(unix)];
+//!         Fmt(::std::fmt::Error);
+//!         Io(::std::io::Error) #[cfg(unix)];
 //!     }
 //!
 //!     // Define additional `ErrorKind` variants. The syntax here is
@@ -171,6 +175,8 @@
 //!         }
 //!     }
 //! }
+//!
+//! # fn main() {}
 //! ```
 //!
 //! Each section, `types`, `links`, `foreign_links`, and `errors` may

tests/tests.rs

@@ -241,7 +241,7 @@ fn chain_err() {
 
     error_chain! {
         foreign_links {
-            fmt::Error, Fmt;
+            Fmt(fmt::Error);
         }
         errors {
             Test
@@ -260,7 +260,7 @@ fn links() {
 
     error_chain! {
         links {
-            test::Error, Test;
+            Test(test::Error);
         }
     }
 }
@@ -314,8 +314,8 @@ mod foreign_link_test {
         }
         links {}
         foreign_links {
-            ForeignError, Foreign;
-            ::std::io::Error, Io;
+            Foreign(ForeignError);
+            Io(::std::io::Error);
         }
         errors {}
     }
@@ -382,11 +382,11 @@ mod attributes_test {
         }
 
         links {
-            inner::Error, Inner, #[cfg(not(test))];
+            Inner(inner::Error) #[cfg(not(test))];
         }
 
         foreign_links {
-            io::Error, Io, #[cfg(not(test))];
+            Io(io::Error) #[cfg(not(test))];
         }
 
         errors {
@@ -426,10 +426,10 @@ fn documentation() {
 
     error_chain! {
         links {
-            inner::Error, Inner, #[doc = "Doc"];
+            Inner(inner::Error) #[doc = "Doc"];
         }
         foreign_links {
-            ::std::io::Error, Io, #[doc = "Doc"];
+            Io(::std::io::Error) #[doc = "Doc"];
         }
         errors {
             /// Doc