signal: use more descriptive template parameter names

signal.hpp

@@ -3,11 +3,10 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  *
- * Copyright 2011-2015 Danny Robson <danny@nerdcruft.net>
+ * Copyright 2011-2019 Danny Robson <danny@nerdcruft.net>
  */
 
-#ifndef CRUFT_UTIL_SIGNAL_HPP
+#pragma once
-#define CRUFT_UTIL_SIGNAL_HPP
 
 #include "types/traits.hpp"
 #include "debug.hpp"
@@ -18,13 +17,13 @@
 #include <list>
 
 namespace cruft {
-    namespace combine {
+    namespace reduce {
-        template <typename F>
+        template <typename FunctionT>
         struct logical_and {
-            using R = typename func_traits<F>::return_type;
+            using result = typename func_traits<FunctionT>::return_type;
 
-            template <typename T, typename ...Args>
+            template <typename InputT, typename ...Args>
-            R operator() (T first, T last, Args&&... args)
+            result operator() (InputT first, InputT last, Args&&... args)
             {
                 while (first != last)
                     if (!(*first++)(args...))
@@ -34,12 +33,12 @@ namespace cruft {
             }
         };
 
-        template <typename F>
+        template <typename FunctionT>
         struct logical_or {
-            using R = typename func_traits<F>::return_type;
+            using result = typename func_traits<FunctionT>::return_type;
 
-            template <typename T, typename ...Args>
+            template <typename InputT, typename ...Args>
-            R operator() (T first, T last, Args&&... args)
+            result operator() (InputT first, InputT last, Args&&... args)
             {
                 while (first != last)
                     if ((*first++)(args...))
@@ -49,12 +48,12 @@ namespace cruft {
             }
         };
 
-        template <typename F>
+        template <typename FunctionT>
         struct noop {
-            using R = void;
+            using result = void;
 
-            template <typename T, typename ...Args>
+            template <typename InputT, typename ...Args>
-            R operator() (T first, T last, Args&&... args)
+            result operator() (InputT first, InputT last, Args&&... args)
             {
                 while (first != last) {
                     (*first++)(args...);
@@ -63,11 +62,14 @@ namespace cruft {
         };
     }
 
-    template <typename F, template <typename> class C = combine::noop>
+    template <
+        typename FunctionT,
+        template <typename> class ReductionT = reduce::noop
+    >
     class signal {
         public:
-            using R = typename C<F>::R;
+            using result = typename ReductionT<FunctionT>::result;
-            using callback = std::function<F>;
+            using callback = std::function<FunctionT>;
 
             struct cookie;
 
@@ -127,18 +129,18 @@ namespace cruft {
             }
 
             /// Execute all callbacks
-            template <typename ...Args>
+            template <typename ...ArgsT>
-            R
+            result
-            operator() (Args&&... tail)
+            operator() (ArgsT&&... tail)
             {
                 if (m_children.empty ())
-                    return R();
+                    return result();
 
-                C<F> combiner;
+                ReductionT<FunctionT> reducer;
-                return combiner (
+                return reducer (
                     m_children.begin (),
                     m_children.end (),
-                    std::forward<Args> (tail)...
+                    std::forward<ArgsT> (tail)...
                 );
             }
 
@@ -149,10 +151,10 @@ namespace cruft {
 
 
     ///////////////////////////////////////////////////////////////////////////
-    template <typename F, template <typename> class C>
+    template <typename FunctionT, template <typename> class ReductionT>
-    struct signal<F,C>::cookie : public nocopy {
+    struct signal<FunctionT,ReductionT>::cookie : public nocopy {
         cookie (typename group::iterator _position,
-                signal<F,C> &_parent):
+                signal<FunctionT,ReductionT> &_parent):
             m_position (_position),
             m_parent (_parent)
         { ; }
@@ -176,24 +178,24 @@ namespace cruft {
         }
 
         typename group::iterator m_position;
-        signal<F,C> &m_parent;
+        signal<FunctionT,ReductionT> &m_parent;
     };
 
 
 
     ///////////////////////////////////////////////////////////////////////////
     // wrap a value in a signal and trigger on assignment
-    //template <typename T, template <typename> class C>
+    //template <typename T, template <typename> class ReductionT>
-    template <typename T>
+    template <typename ValueT>
-    class value_signal : public signal<void(T)> {
+    class value_signal : public signal<void(ValueT)> {
     public:
-        explicit value_signal (T t): m_value (t) { ; }
+        explicit value_signal (ValueT _value): m_value (_value) { ; }
         value_signal () = default;
 
-        operator const T&() const { return m_value; }
+        operator const ValueT&() const { return m_value; }
 
-        value_signal<T>&
+        value_signal<ValueT>&
-        operator= (const T &t)
+        operator= (const ValueT &t)
         {
             m_value = t;
             (*this) (m_value);
@@ -201,8 +203,6 @@ namespace cruft {
         }
 
     private:
-        T m_value;
+        ValueT m_value;
     };
 }
-
-#endif

test/signal.cpp

@@ -75,7 +75,7 @@ void
 test_combiner (cruft::TAP::logger &tap)
 {
     {
-        cruft::signal<bool(void), cruft::combine::logical_and> sig;
+        cruft::signal<bool(void), cruft::reduce::logical_and> sig;
 
         unsigned count = 0;
         auto cookie0 = sig.connect ([&] (void) { ++count; return true; });
@@ -87,7 +87,7 @@ test_combiner (cruft::TAP::logger &tap)
     }
 
     {
-        cruft::signal<bool(void), cruft::combine::logical_and> sig;
+        cruft::signal<bool(void), cruft::reduce::logical_and> sig;
 
         unsigned count = 0;
         auto cookie0 = sig.connect ([&] (void) { ++count; return true; });