Re: [Proposal] Modification to ?: functionality

On Tue, Nov 26, 2013 at 6:41 PM, Paul Dragoonis <dragoonis@gmail.com> wrote: > On Tue, Nov 26, 2013 at 4:58 PM, Chris London <me@chrislondon.co> wrote: > > > On Tue, Nov 26, 2013 at 8:15 AM, Mats Lindh <mats.lindh@gmail.com> > wrote: > > > > > On Tue, Nov 26, 2013 at 3:43 PM, Chris London <me@chrislondon.co> > wrote: > > > > > >> I believe these two statements are functionally equivalent: > > >> > > >> $foo = $foo ? $foo : 'default'; > > >> > > >> $foo = $foo ?: 'default'; > > >> > > > > > > They are. > > > > > > > > > I would like to change it so it also checks for isset() so I propose > the > > >> following would be functionally equivalent: > > >> > > >> $foo = isset($foo) && $foo ? $foo : 'default'; > > >> > > >> $foo = $foo ?: 'default'; > > >> > > > > We can't change the behaviour of ?: that ship has already sailed, we'll > just be hurting existing codebases on upgrading and more user education is > required to understand non-visual changes in syntax like this, lets try to > learn from our mistakes by not changing 'behaviour' anymore. > I disagree, I think removing a case for a Notice is the kind of BC break we can allow, especially in major versions. We should aim at making the language easier to use for day to day cases, and I think this change goes in that direction. > > An alternative syntax that is similar and not ugly would be good since the > ?: behaviour was broken from the start since you still need to run isset() > before running ?: which was the problem we tried to solve in the first > place but it just didn't happen. > > I don't like the @ symbol it's too different from what's already there on > the ternary logic. > > Proposal: $foo = $arr['value'] ?:: ""; > > Thoughts? > > > > > > The would break the assumption that a reference to an uninitialized > value > > > would generate a notice, unless explicitly handled in the logic. > > > > > > While I also would like to have something similar to ?: to handle > default > > > values for array keys, etc., this would change a fundamental assumption > > > that as been in place for many years now. I'm not sure if that's a BC > > break > > > that would be acceptable this late. An alternative operator may be more > > > suitable. > > > > > > > What do you think about using: > > > > $foo = $foo @: 'default'; > > > > and possibly > > > > $foo @= 'default'; > > > > > > > > > > > > The change proposed has also been discussed several times since the > > > implementation of ?:. See the ifsetor-RFC: > > > > > > https://wiki.php.net/rfc/ifsetor > > > > > > It also contains links to the discussion around the feature back then. > > > > > > --mats > > > > > > -- Etienne Kneuss http://www.colder.ch