Merge pull request #416 from matthiasbeyer/libimagerror/into-error

Libimagerror/into error

libimagerror/src/error_gen.rs

@@ -1,9 +1,13 @@
+use into::IntoError;
+
 #[macro_export]
 macro_rules! generate_error_imports {
     () => {
         use std::error::Error;
         use std::fmt::Error as FmtError;
         use std::fmt::{Display, Formatter};
+
+        use $crate::into::IntoError;
     }
 }
 
@@ -41,6 +45,19 @@ macro_rules! generate_error_types {
 
         }
 
+        impl IntoError for $kindname {
+            type Target = $name;
+
+            fn into_error(self) -> Self::Target {
+                $name::new(self, None)
+            }
+
+            fn into_error_with_cause(self, cause: Box<Error>) -> Self::Target {
+                $name::new(self, Some(cause))
+            }
+
+        }
+
         #[derive(Debug)]
         pub struct $name {
             err_type: $kindname,

libimagerror/src/into.rs

@@ -0,0 +1,14 @@
+use std::error::Error;
+
+/// Trait to help converting Error kinds into Error instances
+pub trait IntoError {
+    type Target: Error;
+
+    /// Convert the type into an error with no cause
+    fn into_error(self) -> Self::Target;
+
+    /// Convert the type into an error with cause
+    fn into_error_with_cause(self, cause: Box<Error>) -> Self::Target;
+
+}
+

libimagerror/src/lib.rs

@@ -1,5 +1,6 @@
 #[macro_use] extern crate log;
 extern crate ansi_term;
 
+pub mod into;
 pub mod error_gen;
 pub mod trace;