From c8953c038de7db72bb3fae00384faa8a05d86d69 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Thu, 23 Mar 2017 15:03:15 -0700
Subject: [PATCH] ircd::util: Add non-const overloads to tuple iterations.

---
 include/ircd/util.h | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/include/ircd/util.h b/include/ircd/util.h
index 550f365c1..988bc7995 100644
--- a/include/ircd/util.h
+++ b/include/ircd/util.h
@@ -125,6 +125,14 @@ using custom_ptr = std::unique_ptr<T, std::function<void (T *) noexcept>>;
 //
 // for_each(tuple, [](auto&& elem) { ... });
 
+template<size_t i,
+         class func,
+         class... args>
+typename std::enable_if<i == std::tuple_size<std::tuple<args...>>::value, void>::type
+for_each(std::tuple<args...> &t,
+         func&& f)
+{}
+
 template<size_t i,
          class func,
          class... args>
@@ -144,11 +152,32 @@ for_each(const std::tuple<args...> &t,
 	for_each<i+1>(t, std::forward<func>(f));
 }
 
+template<size_t i = 0,
+         class func,
+         class... args>
+typename std::enable_if<i < std::tuple_size<std::tuple<args...>>::value, void>::type
+for_each(std::tuple<args...> &t,
+         func&& f)
+{
+	f(std::get<i>(t));
+	for_each<i+1>(t, std::forward<func>(f));
+}
+
 
 //
 // Iteration of a tuple until() style: your closure returns true to continue, false
 // to break. until() then remains true to the end, or returns false if not.
 
+template<size_t i,
+         class func,
+         class... args>
+typename std::enable_if<i == std::tuple_size<std::tuple<args...>>::value, bool>::type
+until(std::tuple<args...> &t,
+      func&& f)
+{
+	return true;
+}
+
 template<size_t i,
          class func,
          class... args>
@@ -159,6 +188,16 @@ until(const std::tuple<args...> &t,
 	return true;
 }
 
+template<size_t i = 0,
+         class func,
+         class... args>
+typename std::enable_if<i < std::tuple_size<std::tuple<args...>>::value, bool>::type
+until(std::tuple<args...> &t,
+      func&& f)
+{
+	return f(std::get<i>(t))? until<i+1>(t, std::forward<func>(f)) : false;
+}
+
 template<size_t i = 0,
          class func,
          class... args>