remove Context::Fallible

src/rcore/context.rs

@@ -1,16 +1,12 @@
-use fail::*;
-
 use super::*;
 
 /// Execution context.
 pub trait Context<'a>:
-    FallibleCtx<'a, T = Self::_Tm, Fallible = <Self as Context<'a>>::Fallible>
+    FallibleCtx<'a, T = Self::_Tm>
 {
     /// Type to provide for [Monad]ic representation of computation, mostly that of resolution ([`Resolution`]).
     type _Tm: Monad<'a>;
 
-    type Fallible: MonadFailAny<'a, T = Self::T>;
-
     /// See [`Diagnostic`].
     type D: Diagnostic<'a, Self::T>;