Add StaticTypeInfo trait

src/lib.rs

@@ -129,7 +129,7 @@ pub use self::{
 pub use scale_info_derive::TypeInfo;
 
 /// Implementors return their meta type information.
-pub trait TypeInfo: 'static {
+pub trait TypeInfo {
     /// The type identifying for which type info is provided.
     ///
     /// # Note
@@ -143,10 +143,24 @@ pub trait TypeInfo: 'static {
     fn type_info() -> Type;
 }
 
+/// Convenience trait for implementors, combining `TypeInfo` and `'static` bounds.
+///
+/// # Note
+///
+/// Currently because of the `'static` constraint on [`std::any::TypeId::of`] (see [`MetaType`]),
+/// `TypeInfo` constraints must also be accompanied by a `'static` bound. This trait is useful to
+/// for implementors so only a single constraint is required.
+pub trait StaticTypeInfo: TypeInfo + 'static {}
+
+impl<T> StaticTypeInfo for T
+where
+    T: TypeInfo + 'static,
+{}
+
 /// Returns the runtime bridge to the types compile-time type information.
 pub fn meta_type<T>() -> MetaType
 where
-    T: ?Sized + TypeInfo,
+    T: ?Sized + StaticTypeInfo,
 {
     MetaType::new::<T>()
 }