implemented lexer for a more complex subset of the

monkey language

src/token/type.cpp

@@ -1,5 +1,8 @@
 #include "type.hpp"
 
+#include <array>
+#include <unordered_map>
+
 namespace token {
 
     // Array mapping enum values to their string representations
@@ -18,4 +21,17 @@ namespace token {
         return os << "Unknown";
     }
 
+    static std::unordered_map<std::string, type> keywords{
+        {"fn", type::FUNCTION},
+        {"let", type::LET},
+    };
+
+    type lookup_identifier(std::string ident) {
+        try {
+            return keywords.at(ident);
+        } catch (const std::out_of_range&) {
+            return type::IDENTIFIER;
+        }
+    }
+
 } // namespace token

src/token/type.hpp

@@ -1,8 +1,6 @@
 #pragma once
 
-#include <array>
 #include <ostream>
-#include <string_view>
 
 namespace token {
 
@@ -30,5 +28,6 @@ namespace token {
 #undef X
     };
 
-    std::ostream& operator<<(std::ostream& os, type type);
+    std::ostream& operator<<(std::ostream&, type);
+    type lookup_identifier(std::string);
 } // namespace token