Currently the error_message! macro choose whether to interpret the first
character as Span or as format string based on if it is a literal. While this
does work reliably (a Span can never be a literal, and a literal never a Span)
it might be confusing to a user.
Currently the
error_message!macro choose whether to interpret the firstcharacter as
Spanor as format string based on if it is a literal. While thisdoes work reliably (a Span can never be a literal, and a literal never a Span)
it might be confusing to a user.