Implement division

source/lexer.cpp

@@ -1,5 +1,6 @@
 #include "elna/source/lexer.hpp"
 #include <variant>
+#include <sstream>
 
 namespace elna::source
 {
@@ -194,6 +195,20 @@ namespace elna::source
             || of() == type::factor_operator;
     }
 
+    unexpected_character::unexpected_character(const std::string& character, const source::position position)
+        : error(position), character(character)
+    {
+    }
+
+    std::string unexpected_character::what() const
+    {
+        std::stringstream ss{ "Unexpected character '" };
+
+        ss << character << "'";
+
+        return ss.str();
+    }
+
     source_result lex(const std::string& buffer)
     {
         std::vector<token> tokens;
@@ -278,10 +293,10 @@ namespace elna::source
             }
             else
             {
-                return source_result("Unexpected next character", iterator.position());
+                return source_result(unexpected_character{ std::string{ *iterator }, iterator.position() });
             }
             ++iterator;
         }
-        return source_result(tokens);
+        return source_result(std::move(tokens));
     }
 }