From fa431d5be72dd7934fe4a5673f71c5aaf39ab86c Mon Sep 17 00:00:00 2001
From: Christos Choutouridis <houtouridis.ch@gmail.com>
Date: Thu, 8 Oct 2020 16:02:00 +0300
Subject: [PATCH] DEV: small twists

---
 include/utl/concepts/stl.h      |  4 ++--
 include/utl/dev/dev_iterators.h |  6 +++---
 include/utl/meta/basic.h        |  6 +++---
 include/utl/meta/detection.h    |  2 +-
 include/utl/meta/invoke.h       |  6 +++---
 include/utl/meta/sfinae.h       |  4 ++--
 include/utl/meta/typelist.h     |  3 +++
 test/tests/TmetaBasic.cpp       | 10 +++++-----
 8 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/include/utl/concepts/stl.h b/include/utl/concepts/stl.h
index 35357d7..d4d2906 100644
--- a/include/utl/concepts/stl.h
+++ b/include/utl/concepts/stl.h
@@ -34,7 +34,7 @@ namespace utl {
    template <typename _T1, typename _T2, typename _Ret =_T1>
    using use_if_same_t = meta::eval<
       meta::enable_if<
-         meta::same_<_T1, _T2>::value, _Ret
+         meta::same<_T1, _T2>::value, _Ret
       >
    >;
 
@@ -43,7 +43,7 @@ namespace utl {
     * Same
     */
    template <class T, class U>
-   _utlConcept Same = meta::same_<T, U>::value;
+   _utlConcept Same = meta::same<T, U>::value;
 
 //   template<class T>
 //      _utlConcept Decayed = Same<T, std::decay_t<T>>;
diff --git a/include/utl/dev/dev_iterators.h b/include/utl/dev/dev_iterators.h
index 09e64ff..abd5f40 100644
--- a/include/utl/dev/dev_iterators.h
+++ b/include/utl/dev/dev_iterators.h
@@ -398,7 +398,7 @@ namespace utl {
          typename T::difference_type;
          typename T::pointer;
          typename T::reference;
-         requires same_<
+         requires same<
             typename T::iterator_category,
             std::output_iterator_tag
          >::value;
@@ -675,7 +675,7 @@ namespace utl {
          typename T::difference_type;
          typename T::pointer;
          typename T::reference;
-         requires same_ <
+         requires same <
             typename T::iterator_category,
             std::input_iterator_tag
          >::value;
@@ -960,7 +960,7 @@ namespace utl {
          typename T::difference_type;
          typename T::pointer;
          typename T::reference;
-         requires same_<
+         requires same<
             typename T::iterator_category,
             std::input_iterator_tag
          >::value;
diff --git a/include/utl/meta/basic.h b/include/utl/meta/basic.h
index 0a38d62..c2ef3e9 100644
--- a/include/utl/meta/basic.h
+++ b/include/utl/meta/basic.h
@@ -292,13 +292,13 @@ namespace meta{
    //! \name same
    //! @{
    template<typename T1, typename T2>
-   struct same_ : false_ { };
+   struct same : false_ { };
 
    template<typename Tp>
-   struct same_ <Tp, Tp> : true_ { };
+   struct same <Tp, Tp> : true_ { };
 
    template<typename T1, typename T2>
-   using not_same_ = not_<eval<same_<T1, T2>>>;
+   using not_same = not_<eval<same<T1, T2>>>;
    //! @}
 
    //! @}
diff --git a/include/utl/meta/detection.h b/include/utl/meta/detection.h
index 806397d..993ddcb 100644
--- a/include/utl/meta/detection.h
+++ b/include/utl/meta/detection.h
@@ -179,7 +179,7 @@ namespace meta {
    template <typename Expected,
              template<typename...> class Op, typename... Args >
    using is_detected_exact = eval <
-      same_<Expected, detected_t<Op, Args...>>
+      same<Expected, detected_t<Op, Args...>>
    >;
 
    //! evaluates to true if evaluation of Op<Args...> is \p Expected and to false if not
diff --git a/include/utl/meta/invoke.h b/include/utl/meta/invoke.h
index 24c74c2..1bba1a9 100644
--- a/include/utl/meta/invoke.h
+++ b/include/utl/meta/invoke.h
@@ -140,7 +140,7 @@ namespace meta{
             static nil_ check (...);   //< all other combinations
 
          using type = if_ <
-            not_same_<
+            not_same<
                nil_,
                decltype(check<F>(0))
             >, true_, false_
@@ -419,13 +419,13 @@ namespace meta{
    template <typename T1>
    struct same_as {
       template <typename T2>
-      struct apply : same_<T1, T2> { };
+      struct apply : same<T1, T2> { };
    };
 
    template <typename T1>
    struct not_same_as {
       template <typename T2>
-      struct apply : not_same_<T1, T2> { };
+      struct apply : not_same<T1, T2> { };
    };
 
 }}
diff --git a/include/utl/meta/sfinae.h b/include/utl/meta/sfinae.h
index d537d52..032c68b 100644
--- a/include/utl/meta/sfinae.h
+++ b/include/utl/meta/sfinae.h
@@ -54,12 +54,12 @@ namespace meta {
    //! If same type resolves to _Ret, else SFINAE
    template <typename _T1, typename _T2, typename _Ret =_T1>
    using use_if_same_t = enable_if_t<
-      same_<_T1, _T2>::value, _Ret
+      same<_T1, _T2>::value, _Ret
    >;
    //! If not same type resolves to _Ret, else SFINAE
    template <typename _T1, typename _T2, typename _Ret =_T1>
    using use_if_not_same_t = enable_if_t<
-      !same_<_T1, _T2>::value, _Ret
+      !same<_T1, _T2>::value, _Ret
    >;
    //! If any type (_T1 or _T2) type resolves to _Ret, else to SFINAE
    template <typename T1, typename... Ts>
diff --git a/include/utl/meta/typelist.h b/include/utl/meta/typelist.h
index 86cdc65..6e62651 100644
--- a/include/utl/meta/typelist.h
+++ b/include/utl/meta/typelist.h
@@ -705,6 +705,9 @@ namespace meta {
    using seek = seek_if <List, same_as<T>>;
    //! @}
 
+   template <typename List, typename Pred>
+   using first_if = front<seek_if<List, Pred>>;
+
    //! \name count_if
    //! @{
    namespace count_if_impl {
diff --git a/test/tests/TmetaBasic.cpp b/test/tests/TmetaBasic.cpp
index 1caa9d5..6d39f7c 100644
--- a/test/tests/TmetaBasic.cpp
+++ b/test/tests/TmetaBasic.cpp
@@ -140,9 +140,9 @@ namespace TmetaBasic {
       EXPECT_EQ (true, (std::is_same<true_,  and_<true_, true_, true_>>()));
       EXPECT_EQ (true, (std::is_same<false_, and_<true_, true_, false_>>()));
 
-      EXPECT_EQ (true,  (same_<Foo, Foo>()));
-      EXPECT_EQ (false, (same_<Foo, Bar>()));
-      EXPECT_EQ (true,  (not_same_<Foo, Bar>()));
+      EXPECT_EQ (true,  (same<Foo, Foo>()));
+      EXPECT_EQ (false, (same<Foo, Bar>()));
+      EXPECT_EQ (true,  (not_same<Foo, Bar>()));
 
    }
 
@@ -218,11 +218,11 @@ namespace TmetaBasic {
    /*
     * SFINAE
     */
-   template <typename T, typename =when<same_<T, int>::type::value>>
+   template <typename T, typename =when<same<T, int>::type::value>>
    int check1 (T x) { return x; }
    int check1 (...) { return 0; }
 
-   template <typename T, typename =enable_if_t<same_<T, int>::type::value, void>>
+   template <typename T, typename =enable_if_t<same<T, int>::type::value, void>>
    int check2 (T x) { return x; }
    int check2 (...) { return 0; }