Document what feature everything requires
diff --git a/src/synom.rs b/src/synom.rs
index 9f63d96..d14c3f8 100644
--- a/src/synom.rs
+++ b/src/synom.rs
@@ -41,6 +41,8 @@
//! - [`syn!`](../macro.syn.html)
//! - [`tuple!`](../macro.tuple.html)
//! - [`value!`](../macro.value.html)
+//!
+//! *This module is available if Syn is built with the `"parsing"` feature.*
use proc_macro2::TokenStream;
@@ -54,6 +56,8 @@
/// Refer to the [module documentation] for details about parsing in Syn.
///
/// [module documentation]: index.html
+///
+/// *This trait is available if Syn is built with the `"parsing"` feature.*
pub trait Synom: Sized {
fn parse(input: Cursor) -> PResult<Self>;