From b7d7b83b0d775dbb6edca4dd29206da44b448dcc Mon Sep 17 00:00:00 2001
From: trivernis <trivernis@protonmail.com>
Date: Mon, 14 Mar 2022 21:28:12 +0100
Subject: [PATCH] Add comments to impl_typemap macro

Signed-off-by: trivernis <trivernis@protonmail.com>
---
 src/base.rs                     |  4 +++
 src/lib.rs                      |  2 +-
 src/macros.rs                   | 43 +++++++++++++++++++++++++++------
 src/trait_maps/clone_typemap.rs | 28 +++++++--------------
 src/trait_maps/typemap.rs       | 27 ++++++---------------
 src/typemap_trait.rs            |  2 ++
 6 files changed, 58 insertions(+), 48 deletions(-)

diff --git a/src/base.rs b/src/base.rs
index 953580f..bf7f08b 100644
--- a/src/base.rs
+++ b/src/base.rs
@@ -2,6 +2,10 @@ use multi_trait_object::MultitraitObject;
 use std::any::TypeId;
 use std::collections::HashMap;
 
+/// Base typemap used for implementation but not elsewhere
+/// Each other typemap is just a newtype of this base type with
+/// additional implementation.
+#[doc(hidden)]
 #[derive(Debug, Default)]
 pub(crate) struct TypeMapBase(pub(crate) HashMap<TypeId, MultitraitObject>);
 
diff --git a/src/lib.rs b/src/lib.rs
index a92c966..fc05940 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,7 +1,7 @@
 #![doc=include_str!("../README.md")]
 
 mod base;
-pub(crate) mod macros;
+mod macros;
 #[cfg(test)]
 mod tests;
 mod trait_maps;
diff --git a/src/macros.rs b/src/macros.rs
index ae1a546..fbf1135 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -1,10 +1,14 @@
+/// Macro to create a new trait bound typemap
 #[doc(hidden)]
 #[macro_export]
 macro_rules! impl_typemap {
-    ($map:ident, $key:ty) => {
+    ($( #[$outer:meta] )*
+        $map:ident, $key:ident, $($trt:ident), +) => {
+        $( #[$outer] )*
         pub struct $map($crate::base::TypeMapBase);
+        $crate::impl_typekey!($key, $( $trt )+);
 
-        impl $crate::typemap_trait::TypeMapTrait for $map {
+        impl $crate::TypeMapTrait for $map {
             type Key = $key;
 
             #[inline]
@@ -13,37 +17,60 @@ macro_rules! impl_typemap {
             }
 
             #[inline]
-            fn insert<T: $crate::typemap_trait::TypedKeyTrait<Self::Key>>(
+            fn insert<T: $crate::TypedKeyTrait<Self::Key>>(
                 &mut self,
                 value: T::Value,
             ) {
-                let mto = value.into_mto();
+                let mto = <T::Value as $crate::TypedKeyMto<Self::Key>>::into_mto(value);
                 self.0.insert::<T>(mto);
             }
 
             #[inline]
-            fn get<T: $crate::typemap_trait::TypedKeyTrait<Self::Key>>(&self) -> Option<&T::Value> {
+            fn get<T: $crate::TypedKeyTrait<Self::Key>>(&self) -> Option<&T::Value> {
                 self.0.get::<T>().and_then(|v| v.downcast_ref())
             }
 
             #[inline]
-            fn get_mut<T: $crate::typemap_trait::TypedKeyTrait<Self::Key>>(
+            fn get_mut<T: $crate::TypedKeyTrait<Self::Key>>(
                 &mut self,
             ) -> Option<&mut T::Value> {
                 self.0.get_mut::<T>().and_then(|v| v.downcast_mut())
             }
 
             #[inline]
-            fn remove<T: $crate::typemap_trait::TypedKeyTrait<Self::Key>>(
+            fn remove<T: $crate::TypedKeyTrait<Self::Key>>(
                 &mut self,
             ) -> Option<T::Value> {
                 self.0.remove::<T>().and_then(|v| v.downcast())
             }
 
             #[inline]
-            fn contains_key<T: $crate::typemap_trait::TypedKeyTrait<Self::Key>>(&self) -> bool {
+            fn contains_key<T: $crate::TypedKeyTrait<Self::Key>>(&self) -> bool {
                 self.0.contains_key::<T>()
             }
         }
     };
 }
+
+#[doc(hidden)]
+#[macro_export]
+macro_rules! impl_typekey {
+    ($key:ident, $($trt:ident), +) => {
+        #[doc(hidden)]
+        pub struct $key;
+
+        impl<T> $crate::TypedKeyTrait<$key> for T
+        where
+            T: $crate::TypeMapKey,
+            <T as $crate::TypeMapKey>::Value: $crate::TypedKeyMto<$key> $(+ $trt )+,
+        {
+            type Value = T::Value;
+        }
+
+        impl<T: 'static $(+ $trt )+> $crate::TypedKeyMto<$key> for T {
+            fn into_mto(self) -> multi_trait_object::MultitraitObject {
+                multi_trait_object::create_object!(self $(, dyn $trt )+)
+            }
+        }
+    }
+}
diff --git a/src/trait_maps/clone_typemap.rs b/src/trait_maps/clone_typemap.rs
index 82b22a3..1aa0b45 100644
--- a/src/trait_maps/clone_typemap.rs
+++ b/src/trait_maps/clone_typemap.rs
@@ -1,24 +1,14 @@
 use crate::base::TypeMapBase;
-use crate::{impl_typemap, TypeMapKey, TypedKeyMto, TypedKeyTrait};
-use multi_trait_object::{create_object, MultitraitObject, RawClone, TryClone};
+use crate::impl_typemap;
+use multi_trait_object::{RawClone, TryClone};
 
-pub struct CloneTypeMapKey;
-
-impl<T> TypedKeyTrait<CloneTypeMapKey> for T
-where
-    T: TypeMapKey,
-    <T as TypeMapKey>::Value: TypedKeyMto<CloneTypeMapKey> + Clone,
-{
-    type Value = T::Value;
-}
-
-impl<T: 'static + Clone> TypedKeyMto<CloneTypeMapKey> for T {
-    fn into_mto(self) -> MultitraitObject {
-        create_object!(self, dyn RawClone)
-    }
-}
-
-impl_typemap!(CloneTypeMap, CloneTypeMapKey);
+impl_typemap!(
+    /// A typemap that can be cloned restricting all inner
+    /// types to implement [std::clone::Clone] as well.
+    CloneTypeMap,
+    CloneTypeMapKey,
+    RawClone
+);
 
 impl Clone for CloneTypeMap {
     fn clone(&self) -> Self {
diff --git a/src/trait_maps/typemap.rs b/src/trait_maps/typemap.rs
index 4ea5649..0044b4e 100644
--- a/src/trait_maps/typemap.rs
+++ b/src/trait_maps/typemap.rs
@@ -1,22 +1,9 @@
-use crate::{impl_typemap, TypeMapKey, TypedKeyMto, TypedKeyTrait};
-use multi_trait_object::{create_object, MultitraitObject};
+use crate::impl_typemap;
 use std::any::Any;
 
-#[derive(Eq, PartialEq, Hash)]
-pub struct AnyTypeMapKey;
-
-impl<T> TypedKeyTrait<AnyTypeMapKey> for T
-where
-    T: TypeMapKey,
-    <T as TypeMapKey>::Value: Any,
-{
-    type Value = T::Value;
-}
-
-impl<T: 'static> TypedKeyMto<AnyTypeMapKey> for T {
-    fn into_mto(self) -> MultitraitObject {
-        create_object!(self, dyn Any)
-    }
-}
-
-impl_typemap!(TypeMap, AnyTypeMapKey);
+impl_typemap!(
+    /// A typemap that can store any type (implementing [std::any::Any]).
+    TypeMap,
+    AnyTypeMapKey,
+    Any
+);
diff --git a/src/typemap_trait.rs b/src/typemap_trait.rs
index 51236e8..56ebef5 100644
--- a/src/typemap_trait.rs
+++ b/src/typemap_trait.rs
@@ -9,12 +9,14 @@ pub trait TypeMapKey: 'static {
 
 /// A trait used for restricting values inserted in a type map
 /// using type checking
+#[doc(hidden)]
 pub trait TypedKeyTrait<T>: 'static {
     type Value: TypedKeyMto<T>;
 }
 
 /// A trait used to create a multitrait-object from a given
 /// value with the given guaranteed trait implementations
+#[doc(hidden)]
 pub trait TypedKeyMto<T> {
     fn into_mto(self) -> MultitraitObject;
 }