source: Location: prepare for builtins

compiler/source.py

@@ -12,15 +12,23 @@ logger = Logger(__name__)
 @typecheck
 @dataclass
 class Location:
-    line: int
+    line: int = -1
-    character: int
+    character: int = -1
     file: str = "<none>"
+    internal: bool = False
 
     def __str__(self) -> str:
+        if self.internal:
+            return "<internal>"
         return f"{self.file}:{self.line}:{self.character}"
 
     @typecheck
     def __lt__(self, other: Location) -> bool:
+        if self.internal:
+            return True
+        if other.internal:
+            return False
+
         if self.file != other.file:
             logger.trace(f"{self} is not in the same file as {other}")
             return False