From 3e9b86f33f01f064ddf0dedaa98a30ba72d3f1ad Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Tue, 6 Dec 2016 15:18:49 +1100
Subject: [PATCH] view: add make_cview function

---
 view.hpp |  6 +++++-
 view.ipp | 15 ++++++++++++---
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/view.hpp b/view.hpp
index 2c3775c0..ca6fb705 100644
--- a/view.hpp
+++ b/view.hpp
@@ -50,7 +50,7 @@ namespace util {
         constexpr size_t size (void) const noexcept;
 
         constexpr value_type& operator[] (size_t) noexcept;
-        constexpr value_type& operator[] (size_t) const noexcept;
+        constexpr const value_type& operator[] (size_t) const noexcept;
 
         bool operator== (view) const noexcept;
 
@@ -75,6 +75,10 @@ namespace util {
     auto
     make_view (T&&) = delete;
 
+    template <typename T>
+    auto
+    make_cview (const T&);
+
     bool operator== (const std::string&, view<const char*>);
     bool operator== (const std::string&, view<char*>);
     bool operator== (const std::string&, view<std::string::const_iterator>);
diff --git a/view.ipp b/view.ipp
index 0b526c5d..87ba01d5 100644
--- a/view.ipp
+++ b/view.ipp
@@ -143,7 +143,7 @@ util::view<T>::size (void) const noexcept
 ///////////////////////////////////////////////////////////////////////////////
 template <typename T>
 constexpr
-typename util::view<T>::value_type&
+const typename util::view<T>::value_type&
 util::view<T>::operator[] (size_t idx) const noexcept
 {
     return m_begin[idx];
@@ -184,7 +184,7 @@ template <typename T>
 auto
 util::make_view (T &t)
 {
-    return util::view<decltype(std::begin (t))> { t.begin (), t.end () };
+    return util::view<decltype(std::begin (t))> { std::begin (t), std::end (t) };
 }
 
 
@@ -193,5 +193,14 @@ template <typename T>
 auto
 util::make_view (const T &t)
 {
-    return util::view<decltype(std::cbegin (t))> { t.cbegin (), t.cend () };
+    return util::view<decltype(std::cbegin (t))> { std::cbegin (t), std::cend (t) };
+}
+
+
+//-----------------------------------------------------------------------------
+template <typename T>
+auto
+util::make_cview (const T &t)
+{
+    return util::view<decltype(std::cbegin (t))> { std::cbegin (t), std::cend (t) };
 }