From a07999f7436802f15fc21bebd083006c9e681638 Mon Sep 17 00:00:00 2001
From: Adrian Kummerlaender
Date: Thu, 19 Feb 2015 19:18:48 +0100
Subject: Introduced `Branch` and `Else` pair aliases for usage in `Cond` *
 pure _syntax sugar_ to improve readability of `Cond` conditionals

---
 README.md              |  2 +-
 src/conditional/cond.h |  9 +++++++++
 src/function/apply.h   |  9 ++++-----
 test.cc                | 14 +++++++-------
 4 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/README.md b/README.md
index ba07515..92a1c35 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,7 @@ This library is a expanded reimplementation of my previous attempt at this probl
 
 * guaranteed evaluation during compile time
 * basic math and logic operations
-* conditionals
+* conditionals such as `If` and `Cond`
 * `Cons` constructor for `Pair` type
 * `List` function as helper for `Pair` based list construction
 * basic list operators such as `Nth`, `Length`, `Take` and `Append`
diff --git a/src/conditional/cond.h b/src/conditional/cond.h
index c543449..5f8014f 100644
--- a/src/conditional/cond.h
+++ b/src/conditional/cond.h
@@ -19,6 +19,15 @@ using Cond = Cdr<Eval<
 	detail::find_variadic<detail::cond_predicate, Branches...>
 >>;
 
+template <
+	typename Condition,
+	typename Result
+>
+using Branch = Pair<Condition, Result>;
+
+template <typename Result>
+using Else = Branch<Boolean<true>, Result>;
+
 }
 
 #endif  // TYPEASVALUE_SRC_CONDITIONAL_COND_H_
diff --git a/src/function/apply.h b/src/function/apply.h
index 591fa8a..553ae7f 100644
--- a/src/function/apply.h
+++ b/src/function/apply.h
@@ -18,20 +18,19 @@ template <
 	typename...                 Arguments
 >
 struct Apply : Cond<
-	Pair<
+	Branch<
 		GreaterThan<detail::count_placeholders<Arguments...>, Size<2>>,
 		detail::apply_variadic<Function, Arguments...>
 	>,
-	Pair<
+	Branch<
 		IsEqualValue<detail::count_placeholders<Arguments...>, Size<2>>,
 		detail::apply_pair<Function, Arguments...>
 	>,
-	Pair<
+	Branch<
 		IsEqualValue<detail::count_placeholders<Arguments...>, Size<1>>,
 		detail::apply_single<Function, Arguments...>
 	>,
-	Pair<
-		Boolean<true>,
+	Else<
 		detail::apply_none<Function, Arguments...>
 	>
 > { };
diff --git a/test.cc b/test.cc
index 5742fb2..7a2e963 100644
--- a/test.cc
+++ b/test.cc
@@ -239,9 +239,9 @@ static_assert(
 	std::is_same<
 		tav::Int<2>,
 		tav::Cond<
-			tav::Pair<tav::IsEqualValue<tav::Int<1>, tav::Int<2>>, tav::Int<1>>,
-			tav::Pair<tav::IsEqualValue<tav::Int<2>, tav::Int<2>>, tav::Int<2>>,
-			tav::Pair<tav::IsEqualValue<tav::Int<3>, tav::Int<2>>, tav::Int<3>>
+			tav::Branch<tav::IsEqualValue<tav::Int<1>, tav::Int<2>>, tav::Int<1>>,
+			tav::Branch<tav::IsEqualValue<tav::Int<2>, tav::Int<2>>, tav::Int<2>>,
+			tav::Branch<tav::IsEqualValue<tav::Int<3>, tav::Int<2>>, tav::Int<3>>
 		>
 	>::value,
 	"(cond ((= 1 2) 1) ((= 2 2) 2) ((= 3 2) 3)) != 2"
@@ -251,10 +251,10 @@ static_assert(
 	std::is_same<
 		tav::Int<-1>,
 		tav::Cond<
-			tav::Pair<tav::IsEqualValue<tav::Int<1>, tav::Int<2>>, tav::Int< 1>>,
-			tav::Pair<tav::IsEqualValue<tav::Int<2>, tav::Int<3>>, tav::Int< 2>>,
-			tav::Pair<tav::IsEqualValue<tav::Int<3>, tav::Int<4>>, tav::Int< 3>>,
-			tav::Pair<tav::Boolean<true>,                          tav::Int<-1>>
+			tav::Branch<tav::IsEqualValue<tav::Int<1>, tav::Int<2>>, tav::Int< 1>>,
+			tav::Branch<tav::IsEqualValue<tav::Int<2>, tav::Int<3>>, tav::Int< 2>>,
+			tav::Branch<tav::IsEqualValue<tav::Int<3>, tav::Int<4>>, tav::Int< 3>>,
+			tav::Else<tav::Int<-1>>
 		>
 	>::value,
 	"(cond ((= 1 2) 1) ((= 2 3) 2) ((= 3 4) 3) (else -1)) != -1"
-- 
cgit v1.2.3