On Tue, Aug 10, 2021 at 12:03 AM Simão Afonso
<simao.afo...@powertools-tech.com> wrote:
>
> On 2021-08-09 23:57:42, Chris Angelico wrote:
> > On Mon, Aug 9, 2021 at 10:32 PM Samuel Freilich <sfreil...@google.com>
> > wrote:
> > > Even without it being used in as complicated a way as that it's still not
> > > backward compatible because of the trivial case, as foo.endswith("") is
> > > True.
> >
> > I was talking specifically about the original, which can be depended
> > upon to return True or False. Changing the return value would break
> > anything that depends on that.
> >
> > Not sure what you're referring to.
>
> I think this is the problem:
>
> > >>> "str".endswith("") is True
> > True
> > >>> "" is True
> > <stdin>:1: SyntaxWarning: "is" with a literal. Did you mean "=="?
> > False
>
> Even if you use the return value as a bool, it will flip the result.
Yep, that's also a problem, but I don't understand why my comment
about "can be used eg for indexing" was being quoted for context
there. I was talking about how you could do something like this:
protocol = ("ws:", "wss:")[url.startswith("https:")]
If the return value changes, this breaks.
ChrisA
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