From 27abae9d0190e4a788defd33951dab7955bfec88 Mon Sep 17 00:00:00 2001
From: Daniel Larimer <dlarimer@gmail.com>
Date: Fri, 26 Oct 2012 00:59:30 -0400
Subject: [PATCH] adding tuple impl

---
 include/fc/function.hpp   |  13 ++--
 include/fc/make_fused.hpp |  26 ++++++++
 include/fc/tuple.hpp      | 130 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 165 insertions(+), 4 deletions(-)
 create mode 100644 include/fc/make_fused.hpp
 create mode 100644 include/fc/tuple.hpp

diff --git a/include/fc/function.hpp b/include/fc/function.hpp
index 190a98b..f06033a 100644
--- a/include/fc/function.hpp
+++ b/include/fc/function.hpp
@@ -26,7 +26,7 @@ class function {
     function& operator=( function&& c )      { fc::swap(func,c.func); return *this; }
     
     template<typename... Args2>
-    R operator()( Args2... args2) { return func->call(fc::forward<Args2>(args2)...); }
+    R operator()( Args2... args2)const { return func->call(fc::forward<Args2>(args2)...); }
 
   protected:
 
@@ -78,9 +78,14 @@ template<typename R,typename A1>
 class function<R(A1)> : public function<R,A1> {
   public:
     function(){}
-    template<typename U>
-    function( U&& u ) { *this = fc::forward<U>(u); }
-    //using function<R,A1>::operator=;
+//    template<typename U>
+//    function( U&& u ) { static_assert( sizeof(U) < 0, "tesT"); *this = fc::forward<U>(u); }
+    function( const function<R,A1>& u ):function<R,A1>(u){}
+    function( function<R,A1>&& u ):function<R,A1>(u){}
+    function( const function& u ):function<R,A1>(u.func){}
+    function( function&& u ):function<R,A1>(fc::move(u.func)){}
+
+    using function<R,A1>::operator=;
 };
 
 template<typename R,typename A1,typename A2>
diff --git a/include/fc/make_fused.hpp b/include/fc/make_fused.hpp
new file mode 100644
index 0000000..cc82ff8
--- /dev/null
+++ b/include/fc/make_fused.hpp
@@ -0,0 +1,26 @@
+#pragma once
+#include <fc/tuple.hpp>
+#include <fc/function.hpp>
+
+namespace fc {
+   template<typename R>
+   fc::function<R, fc::tuple<> > make_fused( const fc::function<R>& f ) {
+      return [=]( fc::tuple<> ){ return f(); };
+   }
+   template<typename R,typename A>
+   fc::function<R(fc::tuple<A>) > make_fused( const fc::function<R(A)>& f ) {
+      return [f]( fc::tuple<A> t){ return f(t.a); };
+   }
+   template<typename R,typename A,typename B>
+   fc::function<R(fc::tuple<A,B>) > make_fused( const fc::function<R(A,B)>& f ) {
+      return [f]( fc::tuple<A,B> t){ return f(t.a,t.b); };
+   }
+   template<typename R,typename A,typename B,typename C>
+   fc::function<R(fc::tuple<A,B,C>) > make_fused( const fc::function<R(A,B,C)>& f ) {
+      return [f]( fc::tuple<A,B,C> t){ return f(t.a,t.b,t.c); };
+   }
+   template<typename R,typename A,typename B,typename C,typename D>
+   fc::function<R(fc::tuple<A,B,C,D>) > make_fused( const fc::function<R(A,B,C,D)>& f ) {
+      return [f]( fc::tuple<A,B,C> t){ return f(t.a,t.b,t.c,t.d); };
+   }
+}
diff --git a/include/fc/tuple.hpp b/include/fc/tuple.hpp
new file mode 100644
index 0000000..454aa7d
--- /dev/null
+++ b/include/fc/tuple.hpp
@@ -0,0 +1,130 @@
+#pragma once
+#include <fc/utility.hpp>
+
+namespace fc {
+
+  /**
+   *  Provides a fast-compiling tuple that doesn't use fancy meta-programming
+   *  techniques.  It is limited to 4 parameters which is sufficient for most 
+   *  methods argument lists which is the primary use case for this tuple. Methods
+   *  that require more than 4 parameters are probably better served by defining
+   *  a struct.
+   *
+   *  The members of the tuple are easily visited with a simple visitor functor 
+   *  of the form:
+   *  @code
+   *  struct visitor {
+   *    template<typename MemberType>
+   *    void operator()( MemberType& m );
+   *
+   *    template<typename MemberType>
+   *    void operator()( const MemberType& m );
+   *  };
+   *  @endcode
+   */
+  template<typename A=void, typename B=void,typename C=void, typename D=void>
+  struct tuple { 
+    tuple(){}
+    enum size_enum { size = 4 };
+
+    template<typename AA, typename BB, typename CC, typename DD>
+    tuple( AA&& aa, BB&& bb, CC&& cc, DD&& dd )
+    :a( fc::forward<AA>(aa) ),
+     b( fc::forward<BB>(bb) ),
+     c( fc::forward<CC>(cc) ),
+     d( fc::forward<DD>(dd) )
+     {}
+
+    template<typename V>
+    void visit( V&& v ) { v(a); v(b); v(c); v(d); }
+    template<typename V>
+    void visit( V&& v )const { v(a); v(b); v(c); v(d); }
+
+    A a; 
+    B b; 
+    C c; 
+    D d; 
+  }; 
+
+  template<>
+  struct tuple<> {
+    enum size_enum { size = 0 };
+    template<typename V> 
+    void visit( V&& v)const{};
+  };
+
+  template<typename A>
+  struct tuple<A,void> { 
+    enum size_enum { size = 1 };
+    template<typename AA>
+    tuple( AA&& aa ):a( fc::forward<AA>(aa) ){}
+    tuple( const tuple& t ):a(t.a){}
+    tuple( tuple&& t ):a(t.a){}
+    tuple(){}
+
+    template<typename V>
+    void visit( V&& v ) { v(a); }
+    template<typename V>
+    void visit( V&& v )const { v(a); }
+
+    A a; 
+  };
+
+  template<typename A, typename B>
+  struct tuple<A,B> { 
+    enum size_enum { size = 2 };
+
+    template<typename AA, typename BB>
+    tuple( AA&& aa, BB&& bb )
+    :a( fc::forward<AA>(aa) ),
+     b( fc::forward<BB>(bb) ){}
+
+    tuple(){}
+
+    template<typename V>
+    void visit( V&& v ) { v(a); v(b); }
+    template<typename V>
+    void visit( V&& v )const { v(a); v(b); }
+
+    A a; 
+    B b; 
+  };
+
+  template<typename A, typename B, typename C>
+  struct tuple<A, B, C > {
+    enum size_enum { size = 3 };
+    tuple(){}
+
+    template<typename AA, typename BB, typename CC>
+    tuple( AA&& aa, BB&& bb, CC&& cc )
+    :a( fc::forward<AA>(aa) ),
+     b( fc::forward<BB>(bb) ),
+     c( fc::forward<CC>(cc) )
+     {}
+
+    template<typename V>
+    void visit( V&& v ) { v(a); v(b); v(c); }
+    template<typename V>
+    void visit( V&& v )const { v(a); v(b); v(c); }
+
+    A a; 
+    B b; 
+    C c; 
+  };
+
+  tuple<> make_tuple();
+
+  template<typename A>
+  tuple<A> make_tuple(A&& a){ return tuple<A>( fc::forward<A>(a) ); }
+
+  template<typename A,typename B>
+  tuple<A,B> make_tuple(A&& a, B&& b){ return tuple<A,B>( fc::forward<A>(a), fc::forward<B>(b) ); }
+
+  template<typename A,typename B, typename C>
+  tuple<A,B,C> make_tuple(A&& a, B&& b, C&& c){ return tuple<A,B,C>( fc::forward<A>(a), fc::forward<B>(b), fc::forward<C>(c) ); }
+
+  template<typename A,typename B, typename C,typename D>
+  tuple<A,B,C> make_tuple(A&& a, B&& b, C&& c, D&& d){ 
+    return tuple<A,B,C,D>( fc::forward<A>(a), fc::forward<B>(b), fc::forward<C>(c), fc::forward<D>(d) ); 
+  }
+}