[Python-Dev] Emit SyntaxWarning on unrecognized backslash escapes?

[Chris Angelico]

On Tue, Feb 24, 2015 at 2:44 AM, Guido van Rossum <guido at python.org> wrote:
> I think that's a bit too strong. This has been unquestionably valid, correct
> Python -- it was an intentional feature from the start. It may not have
> turned out great, but I think that before warning loudly about every
> instance of this we should have a silent deprecation (which you can turn
> into a visible warning with a command-line flag or a warnings filter). And
> we should have agreement that we're eventually going to make it a syntax
> error.

Is it at all possible for this to be introduced in the 2.x line, or is
the entire concept of a deprecation period one that has to start with
a minor version?

If it's never going to happen in 2.x, I'll raise this as yet another
reason to get the course and all our students migrated to 3.x, but on
the flip side, it means that we absolutely can't get the benefit until
that jump is made.

ChrisA