From 71111a0c17406c39b3b5ab87a6bf45e972ce2caa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20B=C3=A4renz?= <programming@manuelbaerenz.de>
Date: Mon, 30 Dec 2024 20:01:44 +0100
Subject: [PATCH] Document concatS

---
 automaton/src/Data/Stream.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/automaton/src/Data/Stream.hs b/automaton/src/Data/Stream.hs
index a7669a75..815e7de9 100644
--- a/automaton/src/Data/Stream.hs
+++ b/automaton/src/Data/Stream.hs
@@ -314,6 +314,9 @@ catMaybeS = catMaybes
 
 This function lets a stream control the speed at which it produces data,
 since it can decide to produce any amount of output at every step.
+
+If the original stream outputs an empty list and the buffer is empty,
+it is retried until it produces data.
 -}
 concatS :: (Monad m) => StreamT m [a] -> StreamT m a
 concatS StreamT {state, step} =