Add method for checking whether token can be type

rottlib/src/lexer/lexing.rs

@@ -388,6 +388,22 @@ impl Token {
             Token::BlockComment | Token::Brace(BraceKind::CppBlock) | Token::Error
         )
     }
+
+    /// Returns `true` if this token can appear in type position
+    /// (either a built-in type keyword or an identifier).
+    pub fn is_valid_type_name_token(&self) -> bool {
+        matches!(
+            self,
+            Token::Int
+                | Token::Float
+                | Token::Bool
+                | Token::Byte
+                | Token::String
+                | Token::Array
+                | Token::Name
+                | Token::Identifier
+        )
+    }
 }
 
 /// Consume a /* ... */ block comment with arbitrary nesting