From b1b8af014dd943cf204f9d111ffcf6f36d4084ae Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Sat, 5 Aug 2017 16:01:08 -0700
Subject: [PATCH] Prevent leaving unparsed tokens ignored, throwing error
 instead.

---
 src/main/java/org/nwapw/abacus/parsing/ShuntingYardParser.java | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/nwapw/abacus/parsing/ShuntingYardParser.java b/src/main/java/org/nwapw/abacus/parsing/ShuntingYardParser.java
index e6e930d..5d35032 100644
--- a/src/main/java/org/nwapw/abacus/parsing/ShuntingYardParser.java
+++ b/src/main/java/org/nwapw/abacus/parsing/ShuntingYardParser.java
@@ -164,7 +164,8 @@ public class ShuntingYardParser implements Parser<Match<TokenType>>, PluginListe
         tokens = intoPostfix(new ArrayList<>(tokens));
         if(tokens == null) return null;
         Collections.reverse(tokens);
-        return constructRecursive(tokens);
+        TreeNode constructedTree = constructRecursive(tokens);
+        return tokens.size() == 0 ? constructedTree : null;
     }
 
     @Override