Serhiy Storchaka added the comment: DeprecationWarning is used when we want to remove a feature. It becomes an error in the future. FutureWarning is used when we want change the meaning of a feature instead of removing it. For example re.split(':*', 'a:bc') emits a FutureWarning and returns ['a', 'bc'] because there is a plan to make it returning ['', 'a', 'b', 'c', ''].
I think "a silent warning" means that it should emit a DeprecationWarning or a PendingDeprecationWarning. Since there is no haste, we should use 2-releases deprecation period. After this a deprecation can be changed to a SynataxWarning in 3.8 and to a UnicodeDecodeError (for strings) and a ValueError (for bytes) in 4.0. The latter are converted to SyntaxError by parser. At the end we should get the same behavior as for truncated \x and \u escapes. >>> '\u' File "<stdin>", line 1 SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 0-1: truncated \uXXXX escape >>> b'\x' File "<stdin>", line 1 SyntaxError: (value error) invalid \x escape at position 0 Maybe change a parser to convert warnings to a SyntaxWarning? ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue27364> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com