Merge pull request #24 from Sagichnicht04/main

Dash AST

Author: MarkusEble

src/main/java/com/compiler/ExpressionParser.java

@@ -34,7 +34,14 @@ ASTExprNode getVariableExpr() throws Exception {
     }
 
     ASTExprNode getDashExpr() throws Exception {
-        return getParantheseExpr();
+        ASTExprNode result = getParantheseExpr();
+        while (m_lexer.lookAhead().m_type == Type.TDASH) {
+            Token curToken = m_lexer.lookAhead();
+            m_lexer.advance();
+            ASTExprNode operand = getParantheseExpr();
+            result = new ASTTDashNode(result, operand);
+        }
+        return result;
      }    
 
     ASTExprNode getUnaryExpr() throws Exception {

src/main/java/com/compiler/ast/ASTTDashNode.java

@@ -0,0 +1,24 @@
+package com.compiler.ast;
+
+import com.compiler.TokenIntf;
+
+import java.io.OutputStreamWriter;
+
+public class ASTTDashNode extends ASTExprNode {
+    ASTExprNode m_operand0;
+    ASTExprNode m_operand1;
+    com.compiler.TokenIntf.Type m_operator = TokenIntf.Type.TDASH;
+
+    public ASTTDashNode(ASTExprNode operand0, ASTExprNode operand1) {
+        m_operand0 = operand0;
+        m_operand1 = operand1;
+    }
+
+    public int eval() {
+       int operand0 = m_operand0.eval();
+       int operand1 = m_operand1.eval();
+      return (int) Math.pow(operand0,operand1);
+    }
+
+    public void print(OutputStreamWriter outStream, String indent) throws Exception {}
+}

src/test/java/com/compiler/TestTDashExpr.java

@@ -0,0 +1,13 @@
+package com.compiler;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class TestTDashExpr extends TestExpressionParserBase {
+    @Test
+    public void testTDash() throws Exception {
+        assertEquals((int) Math.pow(16, 2), evalExpression("2^4^2"));
+    }
+}
+