Start echoing parse tree

src/Makefile

@@ -1,6 +1,7 @@
 .PHONY: all clean
 all: deelang
 CC = g++
+CPPFLAGS = -g
 
 lexer.o lexer.h: parser.h lexer.l
 	flex -o lexer.cpp --header-file=lexer.h lexer.l
@@ -13,7 +14,7 @@ parser.h parser.o: parser.y
 	rm parser.cpp
 
 deelang: deelang.cpp lexer.o parser.o syntax.o
-	$(CC) -o $@ $^
+	$(CC) $(CPPFLAGS) -o $@ $^
 
 clean:
 	rm -rf *.o parser.h lexer.h deelang

src/deelang.cpp

@@ -5,7 +5,6 @@
 using namespace std;
 
 int main() {
-  yydebug = 1;
   yyparse();
   
   return 0;

src/parser.y

@@ -1,6 +1,8 @@
 %{
-#include <stdio.h>
+#include <cstdio>
+
 #include "syntax.h"
+
 using namespace std;
 
 int yylex();
@@ -12,7 +14,8 @@ void yyerror(const char* p) { fprintf(stderr, p); }
 %union {
        float num;
        char *sym;
-       Node *node;
+       Node *expr;
+       NodeList *exprlist;
 }
 
 %token <sym> ID
@@ -26,10 +29,11 @@ void yyerror(const char* p) { fprintf(stderr, p); }
 %right GETS
 %left CAT
 %left '+' '-'
-%left '/' '*'
+%left '/' '*'n
 %left MAPS
 
-%nterm <node> expr
+%nterm <expr> expr
+%nterm <exprlist> exprlist
 
 %%
 program:	statements | statements statement;
@@ -55,8 +59,10 @@ expr:		funcdef
 funcdef: 	param MAPS expr | param MAPS block;
 param:	 	ID | '_' | // null production;
 
-funcall: 	ID '(' exprlist ')'
+funcall: 	ID '(' exprlist ')' { print_expression_list($3); }
-exprlist:	exprlist ',' expr | expr | // null production;
+exprlist:	exprlist ',' expr { $1 -> push_back($3); $$ = $1; }
+		| expr { $$ = new NodeList(); $$ -> push_back($1); }
+		| { $$ = NULL; } // null production;
 
 conditional: 	IF expr block elifs
 		| IF expr block elifs ELSE block;

src/syntax.cpp

@@ -1,18 +1,33 @@
-#include <string.h>
+#include <iostream>
-#include <stdlib.h>
+#include <cstring>
+#include <cstdlib>
 
 #include "syntax.h"
 
+using namespace std;
+
 IdNode::IdNode(char * id) {
-  this->id = id;
+  this->id = string(id);
+}
+
+void IdNode::display() {
+  cout << id;
 }
 
 NumNode::NumNode(float num) {
   this->num = num;
 }
 
+void NumNode::display() {
+  
+}
+
 StringNode::StringNode(char *str) {
-  this->string = string;
+  this->stringVal = str;
+}
+
+void StringNode::display() {
+  
 }
 
 OpNode::OpNode(int op, Node *first, Node *second) {
@@ -20,3 +35,13 @@ OpNode::OpNode(int op, Node *first, Node *second) {
   this->first = first;
   this->second = second;
 }
+
+void OpNode::display() {
+  
+}
+
+void print_expression_list(NodeList *list) {
+  for (Node *expr : *list) {
+    expr->display();
+  }
+}

src/syntax.h

@@ -1,13 +1,20 @@
 #ifndef SYNTAX_H
 #define SYNTAX_H
 
-class Node {};
+#include <vector>
+#include <string>
+
+class Node {
+public:
+  virtual void display() = 0;
+};
 
 class IdNode : public Node {
 private:
-  char* id;
+  std::string id;
 public:
   IdNode(char*);
+  virtual void display();
 };
 
 class NumNode : public Node {
@@ -15,13 +22,15 @@ private:
   float num;
 public:
   NumNode(float);
+  virtual void display();
 };
 
 class StringNode : public Node {
 private:
-  char* string;
+  char* stringVal;
 public:
   StringNode(char*);
+  virtual void display();
 };
 
 class OpNode : public Node {
@@ -31,7 +40,11 @@ private:
   Node *second;
 public:
   OpNode(int, Node*, Node*);
+  virtual void display();
 };
 
+class NodeList : public std::vector<Node*>{};
+
+void print_expression_list(NodeList *);
 
 #endif /* SYNTAX_H */