Added Parser

- can parse a basic token list to an AST

Compiler/Parser/Nodes/ConstantNode.cs

@@ -0,0 +1,14 @@
+namespace Compiler.Parser.Nodes
+{
+    public sealed class ConstantNode : Node
+    {
+        public override NodeType NodeType { get; set; }
+        public int value { get; set; }
+
+        public ConstantNode(int value)
+        {
+            this.NodeType = NodeType.ExpressionNode;
+            this.value = value;
+        }
+    }
+}

Compiler/Parser/Nodes/FunctionNode.cs

@@ -0,0 +1,15 @@
+using System;
+
+namespace Compiler.Parser.Nodes
+{
+    public sealed class FunctionNode : Node
+    {
+        public string Name { get; set; }
+        public override NodeType NodeType { get; set; }
+
+        public FunctionNode()
+        {
+            this.NodeType = NodeType.FunctionNode;
+        }
+    }
+}

Compiler/Parser/Nodes/Node.cs

@@ -0,0 +1,15 @@
+using System.Collections.Generic;
+
+namespace Compiler.Parser.Nodes
+{
+    public abstract class Node
+    {
+        public abstract NodeType NodeType { get; set; }
+        public List<Node> Children { get; set; }
+
+        protected Node()
+        {
+            Children = new List<Node>();
+        }
+    }
+}

Compiler/Parser/Nodes/NodeType.cs

@@ -0,0 +1,10 @@
+namespace Compiler.Parser
+{
+    public enum NodeType
+    {
+        ProgramNode,
+        FunctionNode,
+        StatementNode,
+        ExpressionNode
+    }
+}

Compiler/Parser/Nodes/ProgramNode.cs

@@ -0,0 +1,12 @@
+namespace Compiler.Parser.Nodes
+{
+    public sealed class ProgramNode : Node
+    {
+        public override NodeType NodeType { get; set; }
+
+        public ProgramNode()
+        {
+            this.NodeType = NodeType.ProgramNode;
+        }
+    }
+}

Compiler/Parser/Nodes/ReturnNode.cs

@@ -0,0 +1,12 @@
+namespace Compiler.Parser.Nodes
+{
+    public sealed class ReturnNode : Node
+    {
+        public override NodeType NodeType { get; set; }
+
+        public ReturnNode()
+        {
+            this.NodeType = NodeType.StatementNode;
+        }
+    }
+}