Throw exception if getting value of variable out of scope

1 files changed, 3 insertions, 2 deletions

diff --git a/src/main/java/org/zwobble/couscous/interpreter/Environment.java b/src/main/java/org/zwobble/couscous/interpreter/Environment.java
index 5985a94..d748654 100644
--- a/src/main/java/org/zwobble/couscous/interpreter/Environment.java
+++ b/src/main/java/org/zwobble/couscous/interpreter/Environment.java
@@ -18,8 +18,9 @@ public class Environment {
         this.stackFrame = new HashMap<>(stackFrame);
     }
 
-    public InterpreterValue get(int referentId) {
-        return stackFrame.get(referentId).get();
+    public InterpreterValue get(int variableId) {
+        checkVariable(variableId);
+        return stackFrame.get(variableId).get();
     }
 
     public void put(int variableId, InterpreterValue value) {