Improved lexer readabilty and replaced raw new in tree construction

* "new" in Tree::addNode member method was replaced with C++14 std::make_unique
* renamed and constified lexer local variables to increase readabilty
** replaced chunky if-clauses with switch-clauses where appropriate
* updated README.md to mention C++14 requirement

1 files changed, 2 insertions, 3 deletions

diff --git a/src/nodes.cc b/src/nodes.cc
index e75c02b..f15a8c9 100644
--- a/src/nodes.cc
+++ b/src/nodes.cc
@@ -49,12 +49,11 @@ double OperatorNode::solve() {
 			);
 		}
 		case TokenType::OPERATOR_DIVIDE: {
-			double rightChild = this->rightChild->solve();
+			const double rightChild{ this->rightChild->solve() };
 			
 			if ( rightChild != 0 ) {
 				return this->leftChild->solve() / rightChild;
-			}
-			else {
+			} else {
 				throw divide_exception();
 			}
 		}