type ComboBox = {
disabled: &bool,
on_select: &fn(s: string) -> Any,
options: &Array<string>,
selected: &[string, null],
placeholder: &string,
width: &Length
};
val combo_box: fn(
?#selected: &[string, null],
?#on_select: fn(s: string) -> Any,
?#placeholder: &string,
?#width: &Length,
?#disabled: &bool,
options: &Array<string>
) -> Widget