David Schäfer · David Schäfer
--- a/saqc/core/register.py
+++ b/saqc/core/register.py
        itself. Mandatory for multivariate functions.
    """

+    # NOTE:
+    # def outer(func: Callable[Concatenate[SaQC, str, P], SaQC]) -> Callable[Concatenate[SaQC, str | None, P], SaQC]:
+    # This would in theory change the type of field from `str` to `str | None`. Unfortunately
+    # typing.Concatenate injects Keyword only arguments, which makes the typechecker unhappy
+    # with `flagFoo()` and only stops complaining on `flagRange(None)`
--- a/saqc/core/register.py
+++ b/saqc/core/register.py
        @functools.wraps(func)
        def inner(
            saqc,
-            field,
-            *args,
+            field: str | Sequence[str] | None = None,
+            *args: P.args,
            regex: bool = False,
            flag: ExternalFlag | OptionalNone = OptionalNone(),
-            **kwargs,
+            **kwargs: P.kwargs,
        ) -> "SaQC":