8 files changed, 57 insertions, 9 deletions
diff --git a/main/core/parser/ast/ASTNode.java b/main/core/parser/ast/ASTNode.java
index 99bdc06..311314f 100644
--- a/main/core/parser/ast/ASTNode.java
+++ b/main/core/parser/ast/ASTNode.java
@@ -2,6 +2,7 @@ package com.jantuomi.interpreter.main.core.parser.ast;
 
 import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
 import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+import com.jantuomi.interpreter.main.exception.InterpreterException;
 
 import java.util.List;
 
@@ -10,7 +11,7 @@ import java.util.List;
  */
 abstract public class ASTNode {
 
-    public abstract DataContainer evaluate();
+    public abstract DataContainer evaluate() throws InterpreterException;
 
     protected Token source;
 
diff --git a/main/core/parser/ast/AdditionNode.java b/main/core/parser/ast/AdditionNode.java
index a6406ae..0820370 100644
--- a/main/core/parser/ast/AdditionNode.java
+++ b/main/core/parser/ast/AdditionNode.java
@@ -2,6 +2,7 @@ package com.jantuomi.interpreter.main.core.parser.ast;
 
 import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
 import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+import com.jantuomi.interpreter.main.exception.InterpreterException;
 
 import java.util.Arrays;
 import java.util.List;
@@ -16,7 +17,7 @@ public class AdditionNode extends BinaryOperatorNode {
     }
 
     @Override
-    public DataContainer evaluate() {
+    public DataContainer evaluate() throws InterpreterException {
         DataContainer operand1 = lhs.evaluate();
         DataContainer operand2 = rhs.evaluate();
 
diff --git a/main/core/parser/ast/AssignmentNode.java b/main/core/parser/ast/AssignmentNode.java
index bcbff1c..f2e7b8d 100644
--- a/main/core/parser/ast/AssignmentNode.java
+++ b/main/core/parser/ast/AssignmentNode.java
@@ -3,6 +3,7 @@ package com.jantuomi.interpreter.main.core.parser.ast;
 import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
 import com.jantuomi.interpreter.main.core.runtime.State;
 import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+import com.jantuomi.interpreter.main.exception.InterpreterException;
 
 import java.util.Arrays;
 import java.util.List;
@@ -16,7 +17,7 @@ public class AssignmentNode extends BinaryOperatorNode {
     }
 
     @Override
-    public DataContainer evaluate() {
+    public DataContainer evaluate() throws InterpreterException {
         SymbolNode symbol = (SymbolNode) lhs;
         DataContainer rValue = rhs.evaluate();
         State.getInstance().setSymbolValueToScope(
diff --git a/main/core/parser/ast/FunctionBodyNode.java b/main/core/parser/ast/BlockBodyNode.java
index 394710c..671f847 100644
--- a/main/core/parser/ast/FunctionBodyNode.java
+++ b/main/core/parser/ast/BlockBodyNode.java
@@ -3,17 +3,18 @@ package com.jantuomi.interpreter.main.core.parser.ast;
 import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
 import com.jantuomi.interpreter.main.core.parser.datatype.VoidDataContainer;
 import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+import com.jantuomi.interpreter.main.exception.InterpreterException;
 
 /**
  * Created by jan on 17.6.2016.
  */
-public class FunctionBodyNode extends VarargOperatorNode {
-    public FunctionBodyNode(Token token) {
+public class BlockBodyNode extends VarargOperatorNode {
+    public BlockBodyNode(Token token) {
         super(token);
     }
 
     @Override
-    public DataContainer evaluate() {
+    public DataContainer evaluate() throws InterpreterException {
         DataContainer returnValue = new VoidDataContainer();
 
         for (ASTNode node : args) {
diff --git a/main/core/parser/ast/BranchNode.java b/main/core/parser/ast/BranchNode.java
new file mode 100644
index 0000000..d6fb4cf
--- /dev/null
+++ b/main/core/parser/ast/BranchNode.java
@@ -0,0 +1,42 @@
+package com.jantuomi.interpreter.main.core.parser.ast;
+
+import com.jantuomi.interpreter.main.core.parser.datatype.BooleanDataContainer;
+import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
+import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+import com.jantuomi.interpreter.main.exception.InterpreterException;
+
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Created by jan on 17.6.2016.
+ */
+public class BranchNode extends ASTNode {
+
+    private ASTNode expression;
+    private BlockBodyNode branch;
+
+    public BranchNode(Token token, ASTNode expression, BlockBodyNode branch) {
+        super(token);
+        this.expression = expression;
+        this.branch = branch;
+    }
+
+    @Override
+    public DataContainer evaluate() throws InterpreterException {
+        DataContainer ev = expression.evaluate();
+        boolean returnValue = false;
+        if (ev instanceof BooleanDataContainer) {
+            returnValue = ((BooleanDataContainer) ev).getData();
+            if (returnValue) {
+                branch.evaluate();
+            }
+        }
+        return new BooleanDataContainer(returnValue);
+    }
+
+    @Override
+    List<ASTNode> getChildren() {
+        return Arrays.asList(expression, branch);
+    }
+}
diff --git a/main/core/parser/ast/FunctionDefineNode.java b/main/core/parser/ast/FunctionDefineNode.java
index 2402bed..482551f 100644
--- a/main/core/parser/ast/FunctionDefineNode.java
+++ b/main/core/parser/ast/FunctionDefineNode.java
@@ -37,7 +37,7 @@ public class FunctionDefineNode extends VarargOperatorNode {
             SymbolNode argSym = (SymbolNode) arg;
             argumentNames.add(argSym.getName());
         }
-        Function function = new Function(argumentNames, (FunctionBodyNode) body);
+        Function function = new Function(argumentNames, (BlockBodyNode) body);
         State.getInstance().addFunctionToScope(name, function);
 
         return new StringDataContainer("function " + name);
diff --git a/main/core/parser/ast/SubtractionNode.java b/main/core/parser/ast/SubtractionNode.java
index 0865ab1..b234d0d 100644
--- a/main/core/parser/ast/SubtractionNode.java
+++ b/main/core/parser/ast/SubtractionNode.java
@@ -2,6 +2,7 @@ package com.jantuomi.interpreter.main.core.parser.ast;
 
 import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
 import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+import com.jantuomi.interpreter.main.exception.InterpreterException;
 
 import java.util.Arrays;
 import java.util.List;
@@ -15,7 +16,7 @@ public class SubtractionNode extends BinaryOperatorNode {
     }
 
     @Override
-    public DataContainer evaluate() {
+    public DataContainer evaluate() throws InterpreterException {
         DataContainer operand1 = lhs.evaluate();
         DataContainer operand2 = rhs.evaluate();
 
diff --git a/main/core/parser/ast/SymbolNode.java b/main/core/parser/ast/SymbolNode.java
index 4dfb403..c44d41b 100644
--- a/main/core/parser/ast/SymbolNode.java
+++ b/main/core/parser/ast/SymbolNode.java
@@ -3,6 +3,7 @@ package com.jantuomi.interpreter.main.core.parser.ast;
 import com.jantuomi.interpreter.main.core.parser.datatype.DataContainer;
 import com.jantuomi.interpreter.main.core.runtime.State;
 import com.jantuomi.interpreter.main.core.tokenizer.token.Token;
+import com.jantuomi.interpreter.main.exception.InterpreterException;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -38,7 +39,7 @@ public class SymbolNode extends ASTNode {
     }
 
     @Override
-    public DataContainer evaluate() {
+    public DataContainer evaluate() throws InterpreterException {
         List<DataContainer> paramValues = new ArrayList<>();
         if (parameterListNode != null) {
             for (ASTNode param : parameterListNode.getChildren()) {