From e36f7933aba0dc5ea0c1a29d75d5a2c6a734d6e5 Mon Sep 17 00:00:00 2001
From: Jon Magnuson <jon.magnuson@gmail.com>
Date: Fri, 10 Nov 2023 16:29:03 -0600
Subject: [PATCH 1/2] build: add `compile_error!` if no runtime is set

Rust will still throw compiler errors for all the usages of tokio, but
this at least adds some context to the failures, in plain English.
---
 src/lib.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/lib.rs b/src/lib.rs
index f79d3aa..155deab 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -42,3 +42,6 @@ pub use reader::{Line, MuxedLines};
 
 #[cfg(doctest)]
 doc_comment::doctest!("../README.md");
+
+#[cfg(not(any(feature = "tokio")))]
+compile_error!("At least one runtime feature must be enabled from: [\"tokio\"]");

From 9b17424df590345667f0de4f6f7da52e92ee7b14 Mon Sep 17 00:00:00 2001
From: Jon Magnuson <jon.magnuson@gmail.com>
Date: Fri, 10 Nov 2023 16:42:34 -0600
Subject: [PATCH 2/2] doc: add feature flags section to README

Includes a note about how one runtime feature must be enabled.
---
 README.md | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/README.md b/README.md
index f602210..9695ea6 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,13 @@ Add linemux to your `Cargo.toml` with:
 linemux = "0.3"
 ```
 
+### Feature flags
+
+Note that building with `default-features: false` must also be coupled with activating a desired
+runtime (currently just `tokio`, but eventually others will be supported).
+
+- `tokio`: Use the tokio runtime (default).
+
 ## Example
 
 ```rust,no_run