Better errors, comments

src/lexer.h

@@ -1,17 +1,29 @@
+#ifndef LEXER_H
+#define LEXER_H
+
 #include <string>
 #include <optional>
 #include <vector>
 
 namespace Solstice {
+    struct Token {
+        std::string value;
+        int line;
+        std::string lineContent;
+    };
+
     class Lexer {
         std::string input;
+        std::vector<std::string> lines;
         size_t size;
         size_t current;
         std::optional<char> peek(int ahead = 1); 
         std::optional<char> consume();
         public:
         Lexer(std::string in);
-        std::vector<std::string> lex();  
+        std::vector<Token> lex();  
 
     };
 }
+
+#endif