In general, there is lots of code out in the wild that can't be updated for whatever reason, e.g. the person that knows Python left and it needs to continue to work. Weak argument, but cost-benefit I think it comes out ahead. In your example there isn't a reason I can tell why swapping the operands isn't what should be done as Calvin mentioned. The onus is on you to positively demonstrate you require both directions, not him to negatively demonstrate it's never required.

I suggest you confine your proposal to `->` only, as it's currently illegal syntax. You would also want the reflected `__r*__` equivalent of `__arrow__` or `__rarrow__` (`__rrarrow__` if you also need the left-arrow...)

Perhaps broadening the use of it, functions may be able to use it as a pipe operator, e.g. Elixir: https://elixir-lang.org/getting-started/enumerables-and-streams.html#the-pipe-operator

On Mon, Mar 11, 2019 at 2:58 PM francismb <francismb@email.de> wrote:

Hi Greg,

On 3/9/19 1:42 AM, Greg Ewing wrote:
> Do you really want
> to tell them that all their code is now wrong?
Of course not, at least not so promptly. But, would it be still a
problem if the update to a new version (let say from 3.X to next(3.X))
is done through some kind of updater/re-writer/evolver. In that case the
evolver could just add the blanks. What do you think ? Could it work?

Thanks in advance!
--francis
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