diff --git a/.settings/org.eclipse.core.resources.prefs b/.settings/org.eclipse.core.resources.prefs
index 4fd796d..e9441bb 100644
--- a/.settings/org.eclipse.core.resources.prefs
+++ b/.settings/org.eclipse.core.resources.prefs
@@ -1,4 +1,3 @@
 eclipse.preferences.version=1
 encoding//src/main/java=UTF-8
-encoding//target/generated-sources/antlr4=UTF-8
 encoding/<project>=UTF-8
diff --git a/pom.xml b/pom.xml
index e549dfc..1dba529 100644
--- a/pom.xml
+++ b/pom.xml
@@ -9,6 +9,8 @@
   <url>http://maven.apache.org</url>
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <antlr4.visitor>true</antlr4.visitor>
+    <antlr4.listener>false</antlr4.listener>
   </properties>
   <dependencies>
     <dependency>
diff --git a/src/main/java/de/hsrm/compiler/Klang/EvalVisitor.java b/src/main/java/de/hsrm/compiler/Klang/EvalVisitor.java
new file mode 100644
index 0000000..2083b30
--- /dev/null
+++ b/src/main/java/de/hsrm/compiler/Klang/EvalVisitor.java
@@ -0,0 +1,227 @@
+package de.hsrm.compiler.Klang;
+
+import org.antlr.v4.runtime.misc.NotNull;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class EvalVisitor extends KlangBaseVisitor<Value> {
+
+    // used to compare floating point numbers
+    public static final double SMALL_VALUE = 0.00000000001;
+
+    // store variables (there's only one global scope!)
+    private Map<String, Value> memory = new HashMap<String, Value>();
+
+    // assignment/id overrides
+    @Override
+    public Value visitAssignment(KlangParser.AssignmentContext ctx) {
+        String id = ctx.ID().getText();
+        Value value = this.visit(ctx.expr());
+        return memory.put(id, value);
+    }
+
+    @Override
+    public Value visitIdAtom(KlangParser.IdAtomContext ctx) {
+        String id = ctx.getText();
+        Value value = memory.get(id);
+        if(value == null) {
+            throw new RuntimeException("no such variable: " + id);
+        }
+        return value;
+    }
+
+    // atom overrides
+    @Override
+    public Value visitStringAtom(KlangParser.StringAtomContext ctx) {
+        String str = ctx.getText();
+        // strip quotes
+        str = str.substring(1, str.length() - 1).replace("\"\"", "\"");
+        return new Value(str);
+    }
+
+    @Override
+    public Value visitNumberAtom(KlangParser.NumberAtomContext ctx) {
+        return new Value(Double.valueOf(ctx.getText()));
+    }
+
+    @Override
+    public Value visitBooleanAtom(KlangParser.BooleanAtomContext ctx) {
+        return new Value(Boolean.valueOf(ctx.getText()));
+    }
+
+    @Override
+    public Value visitNilAtom(KlangParser.NilAtomContext ctx) {
+        return new Value(null);
+    }
+
+    // expr overrides
+    @Override
+    public Value visitParExpr(KlangParser.ParExprContext ctx) {
+        return this.visit(ctx.expr());
+    }
+
+    @Override
+    public Value visitPowExpr(KlangParser.PowExprContext ctx) {
+        Value left = this.visit(ctx.expr(0));
+        Value right = this.visit(ctx.expr(1));
+        return new Value(Math.pow(left.asDouble(), right.asDouble()));
+    }
+
+    @Override
+    public Value visitUnaryMinusExpr(KlangParser.UnaryMinusExprContext ctx) {
+        Value value = this.visit(ctx.expr());
+        return new Value(-value.asDouble());
+    }
+
+    @Override
+    public Value visitNotExpr(KlangParser.NotExprContext ctx) {
+        Value value = this.visit(ctx.expr());
+        return new Value(!value.asBoolean());
+    }
+
+    @Override
+    public Value visitMultiplicationExpr(@NotNull KlangParser.MultiplicationExprContext ctx) {
+
+        Value left = this.visit(ctx.expr(0));
+        Value right = this.visit(ctx.expr(1));
+
+        switch (ctx.op.getType()) {
+            case KlangParser.MULT:
+                return new Value(left.asDouble() * right.asDouble());
+            case KlangParser.DIV:
+                return new Value(left.asDouble() / right.asDouble());
+            case KlangParser.MOD:
+                return new Value(left.asDouble() % right.asDouble());
+            default:
+                throw new RuntimeException("unknown operator: " + KlangParser.tokenNames[ctx.op.getType()]);
+        }
+    }
+
+    @Override
+    public Value visitAdditiveExpr(@NotNull KlangParser.AdditiveExprContext ctx) {
+
+        Value left = this.visit(ctx.expr(0));
+        Value right = this.visit(ctx.expr(1));
+
+        switch (ctx.op.getType()) {
+            case KlangParser.PLUS:
+                return left.isDouble() && right.isDouble() ?
+                        new Value(left.asDouble() + right.asDouble()) :
+                        new Value(left.asString() + right.asString());
+            case KlangParser.MINUS:
+                return new Value(left.asDouble() - right.asDouble());
+            default:
+                throw new RuntimeException("unknown operator: " + KlangParser.tokenNames[ctx.op.getType()]);
+        }
+    }
+
+    @Override
+    public Value visitRelationalExpr(@NotNull KlangParser.RelationalExprContext ctx) {
+
+        Value left = this.visit(ctx.expr(0));
+        Value right = this.visit(ctx.expr(1));
+
+        switch (ctx.op.getType()) {
+            case KlangParser.LT:
+                return new Value(left.asDouble() < right.asDouble());
+            case KlangParser.LTEQ:
+                return new Value(left.asDouble() <= right.asDouble());
+            case KlangParser.GT:
+                return new Value(left.asDouble() > right.asDouble());
+            case KlangParser.GTEQ:
+                return new Value(left.asDouble() >= right.asDouble());
+            default:
+                throw new RuntimeException("unknown operator: " + KlangParser.tokenNames[ctx.op.getType()]);
+        }
+    }
+
+    @Override
+    public Value visitEqualityExpr(@NotNull KlangParser.EqualityExprContext ctx) {
+
+        Value left = this.visit(ctx.expr(0));
+        Value right = this.visit(ctx.expr(1));
+
+        switch (ctx.op.getType()) {
+            case KlangParser.EQ:
+                return left.isDouble() && right.isDouble() ?
+                        new Value(Math.abs(left.asDouble() - right.asDouble()) < SMALL_VALUE) :
+                        new Value(left.equals(right));
+            case KlangParser.NEQ:
+                return left.isDouble() && right.isDouble() ?
+                        new Value(Math.abs(left.asDouble() - right.asDouble()) >= SMALL_VALUE) :
+                        new Value(!left.equals(right));
+            default:
+                throw new RuntimeException("unknown operator: " + KlangParser.tokenNames[ctx.op.getType()]);
+        }
+    }
+
+    @Override
+    public Value visitAndExpr(KlangParser.AndExprContext ctx) {
+        Value left = this.visit(ctx.expr(0));
+        Value right = this.visit(ctx.expr(1));
+        return new Value(left.asBoolean() && right.asBoolean());
+    }
+
+    @Override
+    public Value visitOrExpr(KlangParser.OrExprContext ctx) {
+        Value left = this.visit(ctx.expr(0));
+        Value right = this.visit(ctx.expr(1));
+        return new Value(left.asBoolean() || right.asBoolean());
+    }
+
+    // log override
+    @Override
+    public Value visitLog(KlangParser.LogContext ctx) {
+        Value value = this.visit(ctx.expr());
+        System.out.println(value);
+        return value;
+    }
+
+    // if override
+    @Override
+    public Value visitIf_stat(KlangParser.If_statContext ctx) {
+
+        List<KlangParser.Condition_blockContext> conditions =  ctx.condition_block();
+
+        boolean evaluatedBlock = false;
+
+        for(KlangParser.Condition_blockContext condition : conditions) {
+
+            Value evaluated = this.visit(condition.expr());
+
+            if(evaluated.asBoolean()) {
+                evaluatedBlock = true;
+                // evaluate this block whose expr==true
+                this.visit(condition.stat_block());
+                break;
+            }
+        }
+
+        if(!evaluatedBlock && ctx.stat_block() != null) {
+            // evaluate the else-stat_block (if present == not null)
+            this.visit(ctx.stat_block());
+        }
+
+        return Value.VOID;
+    }
+
+    // while override
+    @Override
+    public Value visitWhile_stat(KlangParser.While_statContext ctx) {
+
+        Value value = this.visit(ctx.expr());
+
+        while(value.asBoolean()) {
+
+            // evaluate the code block
+            this.visit(ctx.stat_block());
+
+            // evaluate the expression
+            value = this.visit(ctx.expr());
+        }
+
+        return Value.VOID;
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/de/hsrm/compiler/Klang/Klang.java b/src/main/java/de/hsrm/compiler/Klang/Klang.java
index a25a865..69ffe2c 100644
--- a/src/main/java/de/hsrm/compiler/Klang/Klang.java
+++ b/src/main/java/de/hsrm/compiler/Klang/Klang.java
@@ -19,6 +19,7 @@ public class Klang {
     KlangParser parser = new KlangParser(tokens);
 
     ParseTree tree = parser.parse(); // begin parsing at init rule
-    System.out.println(tree.toStringTree(parser)); // print LISP-style tree
+    EvalVisitor visitor = new EvalVisitor();
+    visitor.visit(tree);
   }
 }
diff --git a/src/main/java/de/hsrm/compiler/Klang/Value.java b/src/main/java/de/hsrm/compiler/Klang/Value.java
new file mode 100644
index 0000000..c0d6a39
--- /dev/null
+++ b/src/main/java/de/hsrm/compiler/Klang/Value.java
@@ -0,0 +1,59 @@
+package de.hsrm.compiler.Klang;
+
+public class Value {
+
+  public static Value VOID = new Value(new Object());
+
+  final Object value;
+
+  public Value(Object value) {
+      this.value = value;
+  }
+
+  public Boolean asBoolean() {
+      return (Boolean)value;
+  }
+
+  public Double asDouble() {
+      return (Double)value;
+  }
+
+  public String asString() {
+      return String.valueOf(value);
+  }
+
+  public boolean isDouble() {
+      return value instanceof Double;
+  }
+
+  @Override
+  public int hashCode() {
+
+      if(value == null) {
+          return 0;
+      }
+
+      return this.value.hashCode();
+  }
+
+  @Override
+  public boolean equals(Object o) {
+
+      if(value == o) {
+          return true;
+      }
+
+      if(value == null || o == null || o.getClass() != value.getClass()) {
+          return false;
+      }
+
+      Value that = (Value)o;
+
+      return this.value.equals(that.value);
+  }
+
+  @Override
+  public String toString() {
+      return String.valueOf(value);
+  }
+}
diff --git a/target/classes/de/hsrm/compiler/Klang/EvalVisitor.class b/target/classes/de/hsrm/compiler/Klang/EvalVisitor.class
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index c768ae7..897e220 100644
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diff --git a/target/classes/de/hsrm/compiler/Klang/KlangBaseListener.class b/target/classes/de/hsrm/compiler/Klang/KlangBaseListener.class
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index b5c022d..3218d89 100644
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diff --git a/target/classes/de/hsrm/compiler/Klang/KlangVisitor.class b/target/classes/de/hsrm/compiler/Klang/KlangVisitor.class
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index 0000000..333c1c3
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diff --git a/target/classes/de/hsrm/compiler/Klang/Value.class b/target/classes/de/hsrm/compiler/Klang/Value.class
new file mode 100644
index 0000000..505dfae
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diff --git a/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangBaseListener.java b/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangBaseListener.java
deleted file mode 100644
index 6d0bec9..0000000
--- a/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangBaseListener.java
+++ /dev/null
@@ -1,340 +0,0 @@
-// Generated from de/hsrm/compiler/Klang/Klang.g4 by ANTLR 4.5
-package de.hsrm.compiler.Klang;
-
-import org.antlr.v4.runtime.ParserRuleContext;
-import org.antlr.v4.runtime.misc.NotNull;
-import org.antlr.v4.runtime.tree.ErrorNode;
-import org.antlr.v4.runtime.tree.TerminalNode;
-
-/**
- * This class provides an empty implementation of {@link KlangListener},
- * which can be extended to create a listener which only needs to handle a subset
- * of the available methods.
- */
-public class KlangBaseListener implements KlangListener {
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterParse(KlangParser.ParseContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitParse(KlangParser.ParseContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterBlock(KlangParser.BlockContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitBlock(KlangParser.BlockContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterStat(KlangParser.StatContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitStat(KlangParser.StatContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterAssignment(KlangParser.AssignmentContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitAssignment(KlangParser.AssignmentContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterIf_stat(KlangParser.If_statContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitIf_stat(KlangParser.If_statContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterCondition_block(KlangParser.Condition_blockContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitCondition_block(KlangParser.Condition_blockContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterStat_block(KlangParser.Stat_blockContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitStat_block(KlangParser.Stat_blockContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterWhile_stat(KlangParser.While_statContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitWhile_stat(KlangParser.While_statContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterLog(KlangParser.LogContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitLog(KlangParser.LogContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterNotExpr(KlangParser.NotExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitNotExpr(KlangParser.NotExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterUnaryMinusExpr(KlangParser.UnaryMinusExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitUnaryMinusExpr(KlangParser.UnaryMinusExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterMultiplicationExpr(KlangParser.MultiplicationExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitMultiplicationExpr(KlangParser.MultiplicationExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterAtomExpr(KlangParser.AtomExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitAtomExpr(KlangParser.AtomExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterOrExpr(KlangParser.OrExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitOrExpr(KlangParser.OrExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterAdditiveExpr(KlangParser.AdditiveExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitAdditiveExpr(KlangParser.AdditiveExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterPowExpr(KlangParser.PowExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitPowExpr(KlangParser.PowExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterRelationalExpr(KlangParser.RelationalExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitRelationalExpr(KlangParser.RelationalExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterEqualityExpr(KlangParser.EqualityExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitEqualityExpr(KlangParser.EqualityExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterAndExpr(KlangParser.AndExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitAndExpr(KlangParser.AndExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterParExpr(KlangParser.ParExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitParExpr(KlangParser.ParExprContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterNumberAtom(KlangParser.NumberAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitNumberAtom(KlangParser.NumberAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterBooleanAtom(KlangParser.BooleanAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitBooleanAtom(KlangParser.BooleanAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterIdAtom(KlangParser.IdAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitIdAtom(KlangParser.IdAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterStringAtom(KlangParser.StringAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitStringAtom(KlangParser.StringAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterNilAtom(KlangParser.NilAtomContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitNilAtom(KlangParser.NilAtomContext ctx) { }
-
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void enterEveryRule(ParserRuleContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void exitEveryRule(ParserRuleContext ctx) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void visitTerminal(TerminalNode node) { }
-	/**
-	 * {@inheritDoc}
-	 *
-	 * <p>The default implementation does nothing.</p>
-	 */
-	@Override public void visitErrorNode(ErrorNode node) { }
-}
\ No newline at end of file
diff --git a/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangBaseVisitor.java b/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangBaseVisitor.java
new file mode 100644
index 0000000..955accb
--- /dev/null
+++ b/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangBaseVisitor.java
@@ -0,0 +1,190 @@
+// Generated from de/hsrm/compiler/Klang/Klang.g4 by ANTLR 4.5
+package de.hsrm.compiler.Klang;
+import org.antlr.v4.runtime.misc.NotNull;
+import org.antlr.v4.runtime.tree.AbstractParseTreeVisitor;
+
+/**
+ * This class provides an empty implementation of {@link KlangVisitor},
+ * which can be extended to create a visitor which only needs to handle a subset
+ * of the available methods.
+ *
+ * @param <T> The return type of the visit operation. Use {@link Void} for
+ * operations with no return type.
+ */
+public class KlangBaseVisitor<T> extends AbstractParseTreeVisitor<T> implements KlangVisitor<T> {
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitParse(KlangParser.ParseContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitBlock(KlangParser.BlockContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitStat(KlangParser.StatContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitAssignment(KlangParser.AssignmentContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitIf_stat(KlangParser.If_statContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitCondition_block(KlangParser.Condition_blockContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitStat_block(KlangParser.Stat_blockContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitWhile_stat(KlangParser.While_statContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitLog(KlangParser.LogContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitNotExpr(KlangParser.NotExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitUnaryMinusExpr(KlangParser.UnaryMinusExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitMultiplicationExpr(KlangParser.MultiplicationExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitAtomExpr(KlangParser.AtomExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitOrExpr(KlangParser.OrExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitAdditiveExpr(KlangParser.AdditiveExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitPowExpr(KlangParser.PowExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitRelationalExpr(KlangParser.RelationalExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitEqualityExpr(KlangParser.EqualityExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitAndExpr(KlangParser.AndExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitParExpr(KlangParser.ParExprContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitNumberAtom(KlangParser.NumberAtomContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitBooleanAtom(KlangParser.BooleanAtomContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitIdAtom(KlangParser.IdAtomContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitStringAtom(KlangParser.StringAtomContext ctx) { return visitChildren(ctx); }
+	/**
+	 * {@inheritDoc}
+	 *
+	 * <p>The default implementation returns the result of calling
+	 * {@link #visitChildren} on {@code ctx}.</p>
+	 */
+	@Override public T visitNilAtom(KlangParser.NilAtomContext ctx) { return visitChildren(ctx); }
+}
\ No newline at end of file
diff --git a/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangListener.java b/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangListener.java
deleted file mode 100644
index 9eafcbe..0000000
--- a/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangListener.java
+++ /dev/null
@@ -1,293 +0,0 @@
-// Generated from de/hsrm/compiler/Klang/Klang.g4 by ANTLR 4.5
-package de.hsrm.compiler.Klang;
-import org.antlr.v4.runtime.misc.NotNull;
-import org.antlr.v4.runtime.tree.ParseTreeListener;
-
-/**
- * This interface defines a complete listener for a parse tree produced by
- * {@link KlangParser}.
- */
-public interface KlangListener extends ParseTreeListener {
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#parse}.
-	 * @param ctx the parse tree
-	 */
-	void enterParse(KlangParser.ParseContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#parse}.
-	 * @param ctx the parse tree
-	 */
-	void exitParse(KlangParser.ParseContext ctx);
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#block}.
-	 * @param ctx the parse tree
-	 */
-	void enterBlock(KlangParser.BlockContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#block}.
-	 * @param ctx the parse tree
-	 */
-	void exitBlock(KlangParser.BlockContext ctx);
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#stat}.
-	 * @param ctx the parse tree
-	 */
-	void enterStat(KlangParser.StatContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#stat}.
-	 * @param ctx the parse tree
-	 */
-	void exitStat(KlangParser.StatContext ctx);
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#assignment}.
-	 * @param ctx the parse tree
-	 */
-	void enterAssignment(KlangParser.AssignmentContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#assignment}.
-	 * @param ctx the parse tree
-	 */
-	void exitAssignment(KlangParser.AssignmentContext ctx);
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#if_stat}.
-	 * @param ctx the parse tree
-	 */
-	void enterIf_stat(KlangParser.If_statContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#if_stat}.
-	 * @param ctx the parse tree
-	 */
-	void exitIf_stat(KlangParser.If_statContext ctx);
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#condition_block}.
-	 * @param ctx the parse tree
-	 */
-	void enterCondition_block(KlangParser.Condition_blockContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#condition_block}.
-	 * @param ctx the parse tree
-	 */
-	void exitCondition_block(KlangParser.Condition_blockContext ctx);
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#stat_block}.
-	 * @param ctx the parse tree
-	 */
-	void enterStat_block(KlangParser.Stat_blockContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#stat_block}.
-	 * @param ctx the parse tree
-	 */
-	void exitStat_block(KlangParser.Stat_blockContext ctx);
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#while_stat}.
-	 * @param ctx the parse tree
-	 */
-	void enterWhile_stat(KlangParser.While_statContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#while_stat}.
-	 * @param ctx the parse tree
-	 */
-	void exitWhile_stat(KlangParser.While_statContext ctx);
-	/**
-	 * Enter a parse tree produced by {@link KlangParser#log}.
-	 * @param ctx the parse tree
-	 */
-	void enterLog(KlangParser.LogContext ctx);
-	/**
-	 * Exit a parse tree produced by {@link KlangParser#log}.
-	 * @param ctx the parse tree
-	 */
-	void exitLog(KlangParser.LogContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code notExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterNotExpr(KlangParser.NotExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code notExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitNotExpr(KlangParser.NotExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code unaryMinusExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterUnaryMinusExpr(KlangParser.UnaryMinusExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code unaryMinusExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitUnaryMinusExpr(KlangParser.UnaryMinusExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code multiplicationExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterMultiplicationExpr(KlangParser.MultiplicationExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code multiplicationExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitMultiplicationExpr(KlangParser.MultiplicationExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code atomExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterAtomExpr(KlangParser.AtomExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code atomExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitAtomExpr(KlangParser.AtomExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code orExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterOrExpr(KlangParser.OrExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code orExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitOrExpr(KlangParser.OrExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code additiveExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterAdditiveExpr(KlangParser.AdditiveExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code additiveExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitAdditiveExpr(KlangParser.AdditiveExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code powExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterPowExpr(KlangParser.PowExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code powExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitPowExpr(KlangParser.PowExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code relationalExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterRelationalExpr(KlangParser.RelationalExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code relationalExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitRelationalExpr(KlangParser.RelationalExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code equalityExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterEqualityExpr(KlangParser.EqualityExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code equalityExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitEqualityExpr(KlangParser.EqualityExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code andExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void enterAndExpr(KlangParser.AndExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code andExpr}
-	 * labeled alternative in {@link KlangParser#expr}.
-	 * @param ctx the parse tree
-	 */
-	void exitAndExpr(KlangParser.AndExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code parExpr}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void enterParExpr(KlangParser.ParExprContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code parExpr}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void exitParExpr(KlangParser.ParExprContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code numberAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void enterNumberAtom(KlangParser.NumberAtomContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code numberAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void exitNumberAtom(KlangParser.NumberAtomContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code booleanAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void enterBooleanAtom(KlangParser.BooleanAtomContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code booleanAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void exitBooleanAtom(KlangParser.BooleanAtomContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code idAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void enterIdAtom(KlangParser.IdAtomContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code idAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void exitIdAtom(KlangParser.IdAtomContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code stringAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void enterStringAtom(KlangParser.StringAtomContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code stringAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void exitStringAtom(KlangParser.StringAtomContext ctx);
-	/**
-	 * Enter a parse tree produced by the {@code nilAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void enterNilAtom(KlangParser.NilAtomContext ctx);
-	/**
-	 * Exit a parse tree produced by the {@code nilAtom}
-	 * labeled alternative in {@link KlangParser#atom}.
-	 * @param ctx the parse tree
-	 */
-	void exitNilAtom(KlangParser.NilAtomContext ctx);
-}
\ No newline at end of file
diff --git a/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangParser.java b/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangParser.java
index 59fa897..3ee43ca 100644
--- a/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangParser.java
+++ b/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangParser.java
@@ -102,12 +102,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_parse; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterParse(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitParse(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitParse(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -146,12 +143,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_block; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterBlock(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitBlock(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitBlock(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -209,12 +203,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_stat; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterStat(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitStat(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitStat(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -287,12 +278,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_assignment; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterAssignment(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitAssignment(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitAssignment(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -346,12 +334,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_if_stat; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterIf_stat(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitIf_stat(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitIf_stat(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -422,12 +407,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_condition_block; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterCondition_block(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitCondition_block(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitCondition_block(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -468,12 +450,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_stat_block; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterStat_block(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitStat_block(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitStat_block(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -533,12 +512,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_while_stat; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterWhile_stat(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitWhile_stat(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitWhile_stat(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -578,12 +554,9 @@ public class KlangParser extends Parser {
 		}
 		@Override public int getRuleIndex() { return RULE_log; }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterLog(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitLog(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitLog(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -630,12 +603,9 @@ public class KlangParser extends Parser {
 		}
 		public NotExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterNotExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitNotExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitNotExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class UnaryMinusExprContext extends ExprContext {
@@ -645,12 +615,9 @@ public class KlangParser extends Parser {
 		}
 		public UnaryMinusExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterUnaryMinusExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitUnaryMinusExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitUnaryMinusExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class MultiplicationExprContext extends ExprContext {
@@ -666,12 +633,9 @@ public class KlangParser extends Parser {
 		public TerminalNode MOD() { return getToken(KlangParser.MOD, 0); }
 		public MultiplicationExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterMultiplicationExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitMultiplicationExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitMultiplicationExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class AtomExprContext extends ExprContext {
@@ -680,12 +644,9 @@ public class KlangParser extends Parser {
 		}
 		public AtomExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterAtomExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitAtomExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitAtomExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class OrExprContext extends ExprContext {
@@ -698,12 +659,9 @@ public class KlangParser extends Parser {
 		public TerminalNode OR() { return getToken(KlangParser.OR, 0); }
 		public OrExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterOrExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitOrExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitOrExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class AdditiveExprContext extends ExprContext {
@@ -718,12 +676,9 @@ public class KlangParser extends Parser {
 		public TerminalNode MINUS() { return getToken(KlangParser.MINUS, 0); }
 		public AdditiveExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterAdditiveExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitAdditiveExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitAdditiveExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class PowExprContext extends ExprContext {
@@ -736,12 +691,9 @@ public class KlangParser extends Parser {
 		public TerminalNode POW() { return getToken(KlangParser.POW, 0); }
 		public PowExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterPowExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitPowExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitPowExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class RelationalExprContext extends ExprContext {
@@ -758,12 +710,9 @@ public class KlangParser extends Parser {
 		public TerminalNode GT() { return getToken(KlangParser.GT, 0); }
 		public RelationalExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterRelationalExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitRelationalExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitRelationalExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class EqualityExprContext extends ExprContext {
@@ -778,12 +727,9 @@ public class KlangParser extends Parser {
 		public TerminalNode NEQ() { return getToken(KlangParser.NEQ, 0); }
 		public EqualityExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterEqualityExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitEqualityExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitEqualityExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class AndExprContext extends ExprContext {
@@ -796,12 +742,9 @@ public class KlangParser extends Parser {
 		public TerminalNode AND() { return getToken(KlangParser.AND, 0); }
 		public AndExprContext(ExprContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterAndExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitAndExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitAndExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
@@ -1023,12 +966,9 @@ public class KlangParser extends Parser {
 		public TerminalNode CPAR() { return getToken(KlangParser.CPAR, 0); }
 		public ParExprContext(AtomContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterParExpr(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitParExpr(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitParExpr(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class BooleanAtomContext extends AtomContext {
@@ -1036,48 +976,36 @@ public class KlangParser extends Parser {
 		public TerminalNode FALSE() { return getToken(KlangParser.FALSE, 0); }
 		public BooleanAtomContext(AtomContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterBooleanAtom(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitBooleanAtom(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitBooleanAtom(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class IdAtomContext extends AtomContext {
 		public TerminalNode ID() { return getToken(KlangParser.ID, 0); }
 		public IdAtomContext(AtomContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterIdAtom(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitIdAtom(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitIdAtom(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class StringAtomContext extends AtomContext {
 		public TerminalNode STRING() { return getToken(KlangParser.STRING, 0); }
 		public StringAtomContext(AtomContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterStringAtom(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitStringAtom(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitStringAtom(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class NilAtomContext extends AtomContext {
 		public TerminalNode NIL() { return getToken(KlangParser.NIL, 0); }
 		public NilAtomContext(AtomContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterNilAtom(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitNilAtom(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitNilAtom(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 	public static class NumberAtomContext extends AtomContext {
@@ -1085,12 +1013,9 @@ public class KlangParser extends Parser {
 		public TerminalNode FLOAT() { return getToken(KlangParser.FLOAT, 0); }
 		public NumberAtomContext(AtomContext ctx) { copyFrom(ctx); }
 		@Override
-		public void enterRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).enterNumberAtom(this);
-		}
-		@Override
-		public void exitRule(ParseTreeListener listener) {
-			if ( listener instanceof KlangListener ) ((KlangListener)listener).exitNumberAtom(this);
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			if ( visitor instanceof KlangVisitor ) return ((KlangVisitor<? extends T>)visitor).visitNumberAtom(this);
+			else return visitor.visitChildren(this);
 		}
 	}
 
diff --git a/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangVisitor.java b/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangVisitor.java
new file mode 100644
index 0000000..3ce2539
--- /dev/null
+++ b/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangVisitor.java
@@ -0,0 +1,180 @@
+// Generated from de/hsrm/compiler/Klang/Klang.g4 by ANTLR 4.5
+package de.hsrm.compiler.Klang;
+import org.antlr.v4.runtime.misc.NotNull;
+import org.antlr.v4.runtime.tree.ParseTreeVisitor;
+
+/**
+ * This interface defines a complete generic visitor for a parse tree produced
+ * by {@link KlangParser}.
+ *
+ * @param <T> The return type of the visit operation. Use {@link Void} for
+ * operations with no return type.
+ */
+public interface KlangVisitor<T> extends ParseTreeVisitor<T> {
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#parse}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitParse(KlangParser.ParseContext ctx);
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#block}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitBlock(KlangParser.BlockContext ctx);
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#stat}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitStat(KlangParser.StatContext ctx);
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#assignment}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitAssignment(KlangParser.AssignmentContext ctx);
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#if_stat}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitIf_stat(KlangParser.If_statContext ctx);
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#condition_block}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitCondition_block(KlangParser.Condition_blockContext ctx);
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#stat_block}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitStat_block(KlangParser.Stat_blockContext ctx);
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#while_stat}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitWhile_stat(KlangParser.While_statContext ctx);
+	/**
+	 * Visit a parse tree produced by {@link KlangParser#log}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitLog(KlangParser.LogContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code notExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitNotExpr(KlangParser.NotExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code unaryMinusExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitUnaryMinusExpr(KlangParser.UnaryMinusExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code multiplicationExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitMultiplicationExpr(KlangParser.MultiplicationExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code atomExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitAtomExpr(KlangParser.AtomExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code orExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitOrExpr(KlangParser.OrExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code additiveExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitAdditiveExpr(KlangParser.AdditiveExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code powExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitPowExpr(KlangParser.PowExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code relationalExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitRelationalExpr(KlangParser.RelationalExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code equalityExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitEqualityExpr(KlangParser.EqualityExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code andExpr}
+	 * labeled alternative in {@link KlangParser#expr}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitAndExpr(KlangParser.AndExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code parExpr}
+	 * labeled alternative in {@link KlangParser#atom}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitParExpr(KlangParser.ParExprContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code numberAtom}
+	 * labeled alternative in {@link KlangParser#atom}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitNumberAtom(KlangParser.NumberAtomContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code booleanAtom}
+	 * labeled alternative in {@link KlangParser#atom}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitBooleanAtom(KlangParser.BooleanAtomContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code idAtom}
+	 * labeled alternative in {@link KlangParser#atom}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitIdAtom(KlangParser.IdAtomContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code stringAtom}
+	 * labeled alternative in {@link KlangParser#atom}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitStringAtom(KlangParser.StringAtomContext ctx);
+	/**
+	 * Visit a parse tree produced by the {@code nilAtom}
+	 * labeled alternative in {@link KlangParser#atom}.
+	 * @param ctx the parse tree
+	 * @return the visitor result
+	 */
+	T visitNilAtom(KlangParser.NilAtomContext ctx);
+}
\ No newline at end of file
diff --git a/target/klang-1.0-jar-with-dependencies.jar b/target/klang-1.0-jar-with-dependencies.jar
index b45f168..82685b8 100644
Binary files a/target/klang-1.0-jar-with-dependencies.jar and b/target/klang-1.0-jar-with-dependencies.jar differ
diff --git a/target/klang-1.0.jar b/target/klang-1.0.jar
index c829dd1..d6d3434 100644
Binary files a/target/klang-1.0.jar and b/target/klang-1.0.jar differ
diff --git a/target/maven-status/maven-compiler-plugin/compile/default-compile/inputFiles.lst b/target/maven-status/maven-compiler-plugin/compile/default-compile/inputFiles.lst
index a5ea0b6..2251886 100644
--- a/target/maven-status/maven-compiler-plugin/compile/default-compile/inputFiles.lst
+++ b/target/maven-status/maven-compiler-plugin/compile/default-compile/inputFiles.lst
@@ -1,5 +1,5 @@
-/home/marvin/Documents/university/compiler/antlr_test/klang/klang/src/main/java/de/hsrm/compiler/Klang/Klang.java
-/home/marvin/Documents/university/compiler/antlr_test/klang/klang/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangParser.java
-/home/marvin/Documents/university/compiler/antlr_test/klang/klang/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangBaseListener.java
-/home/marvin/Documents/university/compiler/antlr_test/klang/klang/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangLexer.java
-/home/marvin/Documents/university/compiler/antlr_test/klang/klang/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangListener.java
+/home/marvin/Documents/university/compiler/klang/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangLexer.java
+/home/marvin/Documents/university/compiler/klang/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangBaseVisitor.java
+/home/marvin/Documents/university/compiler/klang/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangParser.java
+/home/marvin/Documents/university/compiler/klang/src/main/java/de/hsrm/compiler/Klang/Klang.java
+/home/marvin/Documents/university/compiler/klang/target/generated-sources/antlr4/de/hsrm/compiler/Klang/KlangVisitor.java