[Python-ideas] PEP 505 (None coalescing operators) thoughts

[Carl Meyer]

On 09/28/2015 01:43 PM, Carl Meyer wrote:
[snip]
> I assume that the short-circuiting would follow the precedence
> order; that is, nothing with looser precedence than member and index
> access would be short-circuited. So, for example,
> 
>     foo?.bar['baz'].spam
> 
> would short-circuit the indexing and the final member access, translating to
> 
>     foo.bar['baz'].spam if foo is not None else None
> 
> but
> 
>     foo?.bar or 'baz'
> 
> would mean
> 
>     (foo.bar if foo is not None else None) or 'baz'
> 
> and would never evaluate to None. Similarly for any operator that binds
> less tightly than member/index access (which is basically all Python
> operators).

For a possibly less-intuitive example of this principle (arbitrarily
picking the operator that binds next-most-tightly), what should

    foo?.bar**3

mean?

Carl

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