mode

src/SUMMARY.md

@@ -2,7 +2,7 @@
 
 [Introduction](./ch00/s00-introduction.md)
 
-- [Background]()
+- [Mode Parsing](./ch01/s00-mode-parsing.md)
 - [Implementation]()
 - [Usage]()
 - [Current Implementation Concerns](./ch04/s00-concerns.md)

src/ch01/s00-mode-parsing.md

@@ -0,0 +1,53 @@
+# `Mode` Parsing
+
+```rust
+type ParseSuccess<M, A, I> = <M as Mode>::ParseSuccess<A, I>;
+
+type ModeResult<M, A, E, I> = Result<ParseSuccess<M, A, I>, E>;
+
+trait Mode {
+    type ParseSuccess<A, I>;
+
+    type ExtensionResult<A, E>;
+
+    type ExtensionSource<A>;
+
+    fn bind<A0, A1, E, I>(
+        s: Self::ParseSuccess<A0, I>,
+        f: impl FnOnce(A0) -> Result<A1, E>,
+    ) -> ModeResult<Self, A1, E, I>;
+
+    fn map<A0, A1, I>(
+        s: Self::ParseSuccess<A0, I>,
+        f: impl FnOnce(A0) -> A1,
+    ) -> Self::ParseSuccess<A1, I>;
+
+    fn seal<A, I>(s: Self::ParseSuccess<A, I>) -> A;
+
+    fn xmap_err<A, E0, E1>(
+        result: Self::ExtensionResult<A, E0>,
+        f: impl FnOnce(E0) -> E1,
+    ) -> Self::ExtensionResult<A, E1>;
+
+    fn xbind<A0, A1, E>(
+        result: Self::ExtensionResult<A0, E>,
+        f: impl FnOnce(A0) -> Result<A1, E>,
+    ) -> Self::ExtensionResult<A1, E>;
+
+    fn xseal<A, E>(result: Self::ExtensionResult<A, E>) -> Result<A, E>;
+
+    fn smap<A0, A1>(
+        source: Self::ExtensionSource<A0>,
+        f: impl FnOnce(A0) -> A1,
+    ) -> Self::ExtensionSource<A1>;
+
+    fn prepare<A>(a: A) -> Self::ExtensionSource<A>;
+
+    fn xsbind<AB, A, B, E>(
+        ab: Self::ExtensionSource<AB>,
+        t2ab: impl FnOnce(AB) -> (A, B),
+        ce: impl FnOnce(Self::ExtensionSource<B>) -> Self::ExtensionResult<B, E>,
+        ab2t: impl FnOnce(A, B) -> Result<AB, E>,
+    ) -> Self::ExtensionResult<AB, E>;
+}
+```