read explicit lifetime to FromDsl

dsl/src/dsl_provide.rs

@@ -18,10 +18,10 @@ pub trait Dsl<Other>: Sized {
         }
     }
 }
-pub trait FromDsl<State>: Sized {
-    fn take_from <'state, 'source: 'state> (state: &'state State, token: &mut TokenIter<'source>)
+pub trait FromDsl<'source, State>: Sized {
+    fn take_from <'state> (state: &'state State, token: &mut TokenIter<'source>)
         -> Perhaps<Self>;
-    fn take_from_or_fail <'state, 'source: 'state> (
+    fn take_from_or_fail <'state> (
         state: &'state State,
         token: &mut TokenIter<'source>,
         error: impl Into<Box<dyn std::error::Error>>
@@ -33,13 +33,6 @@ pub trait FromDsl<State>: Sized {
         }
     }
 }
-impl<T: FromDsl<State>, State> Dsl<T> for State {
-    fn take <'state, 'source: 'state> (&'state self, token: &mut TokenIter<'source>)
-        -> Perhaps<T>
-    {
-        FromDsl::take_from(self, token)
-    }
-}
 //impl<State: Dsl<T>, T> FromDsl<State> for T {
     //fn take_from <'state, 'source: 'state> (state: &'state State, token: &mut TokenIter<'source>)
         //-> Perhaps<Self>
@@ -51,16 +44,36 @@ impl<T: FromDsl<State>, State> Dsl<T> for State {
 /// Implement the [Dsl] trait, which boils down to
 /// specifying two types and providing an expression.
 #[macro_export] macro_rules! from_dsl {
-    ($T:ty: |$state:ident:$S:ty, $words:ident|$expr:expr) => {
-        impl ::tengri::dsl::FromDsl<$S> for $T {
-            fn take_from <'state, 'source: 'state> (
-                $state: &'state $S,
-                $words: &mut ::tengri::dsl::TokenIter<'source>,
-            ) -> ::tengri::Perhaps<$T> {
+    (@a: $T:ty: |$state:ident, $words:ident|$expr:expr) => {
+        impl<'source, State: Dsl<A>, A> FromDsl<'source, State> for $T {
+            fn take_from <'state> (
+                $state: &'state State,
+                $words: &mut TokenIter<'source>,
+            ) -> Perhaps<$T> {
                 $expr
             }
         }
-    }
+    };
+    (@ab: $T:ty: |$state:ident, $words:ident|$expr:expr) => {
+        impl<'source, State: Dsl<A> + Dsl<B>, A, B> FromDsl<'source, State> for $T {
+            fn take_from <'state> (
+                $state: &'state State,
+                $words: &mut TokenIter<'source>,
+            ) -> Perhaps<$T> {
+                $expr
+            }
+        }
+    };
+    ($T:ty: |$state:ident:$S:ty, $words:ident|$expr:expr) => {
+        impl<'source> FromDsl<'source, $S> for $T {
+            fn take_from <'state> (
+                $state: &'state $S,
+                $words: &mut TokenIter<'source>,
+            ) -> Perhaps<$T> {
+                $expr
+            }
+        }
+    };
 }
 
 ///// Maps a sequencer of EDN tokens to parameters of supported types