fixed scanner.hpp

src/main.cpp

@@ -1,4 +1,5 @@
 #include "../build/parser.hpp"
+#include "../src/scanner.hpp"
 
 int main()
 {

src/scanner.cpp

@@ -0,0 +1,7 @@
+#include "../src/scanner.hpp"
+
+int scanner_lex(yy::parser::semantic_type *yylval)
+{
+    static Scanner scanner(&std::cin);
+    return scanner.lex(yylval);
+}

src/scanner.hpp

@@ -1,4 +1,10 @@
 #pragma once
+
+// fucking piece of shit flex, doesn't even have proper macro directives
+#ifndef yyFlexLexer
+#include <FlexLexer.h>
+#endif
+
 #include "../build/parser.hpp"
 #include <string>
 
@@ -9,8 +15,6 @@ class Scanner : public yyFlexLexer
 public:
     Scanner(std::istream *in) : yyFlexLexer(in) {}
 
-    int yylex();
-
     int lex(yy::parser::semantic_type *yylval)
     {
         this->yylval = yylval;
@@ -18,11 +22,8 @@ public:
     }
 
 private:
+    virtual int yylex();
     yy::parser::semantic_type *yylval;
 };
 
-int scanner_lex(yy::parser::semantic_type *yylval)
-{
-    static Scanner scanner(&std::cin);
-    return scanner.lex(yylval);
-}
+int scanner_lex(yy::parser::semantic_type *yylval);