From 3425d6bb0036740ab0639574a201802bb2c2a822 Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@gmail.com>
Date: Sun, 8 Dec 2019 05:22:04 +0200
Subject: [PATCH] Fix mp_eval_if_c example; add one for mp_eval_or

---
 doc/mp11/utility.adoc | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/doc/mp11/utility.adoc b/doc/mp11/utility.adoc
index fcd1a61..1221242 100644
--- a/doc/mp11/utility.adoc
+++ b/doc/mp11/utility.adoc
@@ -113,7 +113,7 @@ is to avoid evaluating `F<U...>` when the condition is `true` as it may not be v
 .Using mp_eval_if_c to select the first pack element, or void
 ```
 template<class... T> using first_or_void =
-    mp_eval_if_c<sizeof...(T) == 0, void, mp_apply, mp_first, mp_list<T...>>;
+    mp_eval_if_c<sizeof...(T) == 0, void, mp_first, mp_list<T...>>;
 ```
 
 ## mp_eval_if<C, T, F, U...>
@@ -175,6 +175,12 @@ Like `mp_valid`, but takes a quoted metafunction.
 
 `mp_eval_or<T, F, U...>` is an alias for `F<U...>` when this expression is valid, for `T` otherwise.
 
+.Using mp_eval_or to select the first pack element, or void
+```
+template<class... T> using first_or_void =
+    mp_eval_or<void, mp_first, mp_list<T...>>;
+```
+
 ## mp_eval_or_q<T, Q, U...>
 
     template<class T, class Q, class... U> using mp_eval_or_q =