[Python-Dev] Surely "nullable" is a reasonable name?

[Nick Coghlan]

On 25 April 2015 at 17:58, Larry Hastings <larry at hastings.org> wrote:
>
> On 04/24/2015 09:45 PM, Nick Coghlan wrote:
>
> Ah, I misread Tal's suggestion. Using unary + is an even neater approach.
>
>
> Not exactly.  The way I figure it, the best way to achieve this with unary
> plus is to ast.parse it (as we currently do) and then modify the parse tree.
> That works but it's kind of messy.
>
> My main objection to this notation is that that set objects don't support +.
> The union operator for sets is |.

Good point.

> I've prototyped a hack allowing
>     str(accept|={NoneType})
> I used the tokenize module to tokenize, modify, and untokenize the converter
> invocation.  Works fine.  And since augmented assignment is (otherwise)
> illegal in expressions, it's totally unambiguous.  I think if we do it at
> all it should be with that notation.

I'd say start without it, but if it gets annoying, then we have this
in our back pocket as a potential fix.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia