effect docs

src/func/instances.rs

@@ -4,7 +4,7 @@
 //!
 //! For [`MonadFail<E>`] examples, see [`result`][^research].
 //!
-//! For the simplest form (even ChatGPT can understand it! lol) of [`Monad`], see [`solo`][^production].
+//! For the simplest form of [`Monad`], see [`solo`][^production].
 //!
 //! For async support, see [`future`][^production][^research] and [`tryfuture`][^production][^research].
 //!
@@ -12,6 +12,8 @@
 //!
 //! For combining monads, see [`composition`][^research].
 //! 
+//! For adding extra metadata to values, see [`effect`][^research].
+//!
 //! [^production]: instances expected to be used in production.
 //!
 //! [^research]: instances used for research purposes to enhance the abstract interfaces.

src/func/instances/effect.rs

@@ -1,13 +1,20 @@
+//! [Monad] for passing and combining metadata related to the evaluation of values.
+
 use crate::func::*;
 
+/// Metadata type.
 pub trait Effect {
+    /// Used in [`Pure::pure`].
     fn e_pure() -> Self;
 
+    /// Used in [`ApplicativeLA2::la2`] and other [`Applicative`] methods.
     fn e_seq(lhs: Self, rhs: Self) -> Self;
 
+    /// Used in [`Monad::bind`] and other [`Monad`] methods.
     fn e_after(self, effect: Self) -> Self;
 }
 
+/// Value and related metadata.
 #[derive(Clone)]
 pub struct WithEffect<A, E> {
     pub value: A,