Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On Mon, Dec 15, 2014 at 8:56 AM, Derick Rethans der...@php.net wrote: On Sun, 14 Dec 2014, George Bond wrote: If you wanted an upgrade path that was not Evil (in the sense of not introducing subtle and hard-to-diagnose bugs), could you not change the operator to be *un*associative in PHP7? That would effectively just make concrete the discouragement/deprecation that's already in the documentation, and would produce irritating but very visible errors for anyone still actually using this functionality, as well as making them alter their code in a forward-compatible way. Then if you want to think really long term, plan to implement the 'correct' associativity in the *next* major version. As long as this unassociativity turns it into a hard syntax error (ie, php -l will catch it out), I am not against this. I'm with Derick. We either don't change the implicit associativity, or we make ambiguous statements a parse error with a clear link to the documentation explaining to add parens in order to make the associativity explicit. -Sara -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
Hi! Precisely why I suggested we do a poll and find out. Polling is a valid means of getting a reasonable accounting of a particular metric. If you do it in a professional way, with properly randomized samples, controlled statistics, etc. Putting a form on the internet and counting people who may have by chance stumbled upon it or were directed to it by promoters of certain position doesn't do that. If we use a sufficiently diverse and representative sample, we should easily be able to get accurate enough results to settle this question once and for all. If. -- Stas Malyshev smalys...@gmail.com -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
Hi all, On Tue, Dec 16, 2014 at 6:17 PM, Stanislav Malyshev smalys...@gmail.com wrote: Precisely why I suggested we do a poll and find out. Polling is a valid means of getting a reasonable accounting of a particular metric. If you do it in a professional way, with properly randomized samples, controlled statistics, etc. Putting a form on the internet and counting people who may have by chance stumbled upon it or were directed to it by promoters of certain position doesn't do that. Instead of polling people, how about provide a compatibility check script? This would be easy with tokenizer, I suppose. Regards, -- Yasuo Ohgaki yohg...@ohgaki.net
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On Tue, Dec 16, 2014 at 06:48:14PM +0900, Yasuo Ohgaki wrote: Instead of polling people, how about provide a compatibility check script? This would be easy with tokenizer, I suppose. +1 -- Alain Williams Linux/GNU Consultant - Mail systems, Web sites, Networking, Programmer, IT Lecturer. +44 (0) 787 668 0256 http://www.phcomp.co.uk/ Parliament Hill Computers Ltd. Registration Information: http://www.phcomp.co.uk/contact.php #include std_disclaimer.h -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On Sun, 14 Dec 2014, George Bond wrote: If you wanted an upgrade path that was not Evil (in the sense of not introducing subtle and hard-to-diagnose bugs), could you not change the operator to be *un*associative in PHP7? That would effectively just make concrete the discouragement/deprecation that's already in the documentation, and would produce irritating but very visible errors for anyone still actually using this functionality, as well as making them alter their code in a forward-compatible way. Then if you want to think really long term, plan to implement the 'correct' associativity in the *next* major version. As long as this unassociativity turns it into a hard syntax error (ie, php -l will catch it out), I am not against this. cheers, Derick -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On Dec 14, 2014, at 23:50, Leon Sorokin leeon...@gmail.com wrote: On 12/14/2014 10:45 PM, Robert Williams wrote: I strongly suspect far more code would be *fixed* if the ternary operator were changed to match what other languages do. If you have 'incorrectly' functioning code today that results in passing unit tests and a correctly functioning business. Then a sudden change to the behavior of this code would necessarily result in failing unit tests and an incorrectly functioning business. What world is this that you live in where every line of code that’s written is fully unit-tested, where functional bugs in large, highly complex applications are both obvious and immediately apparent? In my world, I’ve inherited millions of lines of legacy code written seemingly to defy the possibility of unit testing, where there are large chunks of code that may run once every several years, and where many types of logic bugs are simply undetectable unless a team of auditors on the business side is double-checking every result of the code. Sure, I also have a million or two lines of newer code that is heavily unit-tested, but even that code has bugs. Given that we have this bug to begin with (and yes, it’s a bug), as well as many of the others that have worked their way into the PHP code base, it strikes me that PHP itself is written in my world, not yours. Hey, reality bites. Also, code that is thoroughly unit-tested is not the code we need to worry about for the very reasons you espouse. If the ternary behavior is changed, the one or two bugs that may be introduced in every several hundred K LOC will become immediately apparent on first test-run and probably be fixed in 30 minutes or less. It’s the crappy code that we have to worry about, the code that’s broken and no one even knows about it. In these cases, I maintain, fixing ternary would only improve the code’s functioning. -Bob -- Bob Williams SVP, Software Development Newtek Business Services, Inc. “The Small Business Authority” http://www.thesba.com/ Notice: This communication, including attachments, may contain information that is confidential. It constitutes non-public information intended to be conveyed only to the designated recipient(s). If the reader or recipient of this communication is not the intended recipient, an employee or agent of the intended recipient who is responsible for delivering it to the intended recipient, or if you believe that you have received this communication in error, please notify the sender immediately by return e-mail and promptly delete this e-mail, including attachments without reading or saving them in any manner. The unauthorized use, dissemination, distribution, or reproduction of this e-mail, including attachments, is prohibited and may be unlawful. If you have received this email in error, please notify us immediately by e-mail or telephone and delete the e-mail and the attachments (if any).
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
Leon Sorokin wrote on 13/12/2014 22:45: Hi guys, I was wondering if 7.0 could be the version to fix the long-standing incorrect ternary associativity bug in PHP [1]. This seems especially worthy of reconsideration since the Null Coalesce RFC has been accepted and merged [2] with the correct associativity [3]. The major version change seems like the only time to get this done in PHP. [1] https://bugs.php.net/bug.php?id=61915 [2] https://wiki.php.net/rfc/isset_ternary [3] http://news.php.net/php.internals/79584 thanks, -- Leon Sorokin Actually, thinking further on this, I'm not sure I've ever actually been affected by the associativity of ?: one way or the other. I have fallen foul of its precedence relative to concatenation, as in: echo 'hello' . false ? ' world' : ' there' . '!'; http://3v4l.org/i7cSc But I think this is the same in other languages, and not related to this bug? Regards, -- Rowan Collins [IMSoP] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
Hi! The fact that it *may* break *some* code that is used somewhere despite documentation recommending against it (pretty much deprecating it already for years) is a terrible reason not to re-evaluate the situation given the huge opportunity to correct this. It *will* break some code. There's no chance that somebody somewhere doesn't use this. And the change would break it. Worse yet, he won't be able to know about it until the customer complains about code logic being broken. The only thing that's bonkers here is outright refusal to make trivially breaking changes (in addition to numerous other breaking changes already accepted) simply for the sake of not breaking some 0.1% of outdated, There's not that many breaking changes accepted, and each of them had to be substantiated. We had other breaking changes is not a substantiation. For example, most uses of associativity are wrong ones - is, but that makes the idea of un-associating it even better, since unlike changing the associativity, it actually makes the problem obvious and easy to fix. Alternatively, of course, we could make a tool that detects this and alerts the user, but making it loud still sounds better. And the breakage we are discussing is not trivial - it's a logic change which makes code silently take different codepath without anybody knowing. In the world of BC breaks, this is one of the most evil ones. So we should avoid it as much as possible. Rather than simply pointing to a 3-year-old close-reason, it would be prudent to actually get statistics on how often this unexpected behavior is relied upon in large, popular codebases. Packagist Github, that Usually the burden of proof lays on whoever proposes the change. Note that a lot of code is not public, especially for languages like PHP that is used for websites - meaning, there's little reason to publicize any code but reusable library code. And the fact that the change would not break a handful of popular libraries doesn't mean it won't break scores of websites whose source you can not see, but which are way more important for the people using them than some library they don't use. Yes, I understand that this means very high burden on somebody proposing BC-breaking change, and it makes the development more conservative. It is a high burden convince people that this change is worth the risk of breaking potentially unknown code with unknown consequences. I think, however, it's better than actually suffering these consequences. Consider that however ugly this particular wart is, people has been living with it for almost 20 years, and it may be preferable for them to have somewhat ugly code than having broken code. It's short responses like this and the continued reliance on arguments posed in a different era/landscape that compel me to reconsider my continued participation in the PHP community at all. Sorry, but arguing from do this or that or I'm quitting does not seem a very strong argument to me. More drama does not help to evaluate the merits of changing the associativity of ?:. I think everybody here values the time of the volunteers that continue to contribute to the project, but I think keeping the discussion on the technical merits would be better. -- Stas Malyshev smalys...@gmail.com -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On Mon, Dec 15, 2014 at 12:11 PM, Stanislav Malyshev smalys...@gmail.com wrote: Hi! The fact that it *may* break *some* code that is used somewhere despite documentation recommending against it (pretty much deprecating it already for years) is a terrible reason not to re-evaluate the situation given the huge opportunity to correct this. It *will* break some code. There's no chance that somebody somewhere doesn't use this. And the change would break it. Worse yet, he won't be able to know about it until the customer complains about code logic being broken. On what basis are you making that claim with such certitude? In all my years, I have yet to encounter a single, solitary case where someone's actually relying on PHP's wonky, counter-intuitive, non-standard associativity with the ternary operator. If such a one-in-a-billion scripts does exist somewhere, it's likely some PHP 4 thing that hasn't been touched in years. The only thing that's bonkers here is outright refusal to make trivially breaking changes (in addition to numerous other breaking changes already accepted) simply for the sake of not breaking some 0.1% of outdated, There's not that many breaking changes accepted, and each of them had to be substantiated. We had other breaking changes is not a substantiation. For example, most uses of associativity are wrong ones - is, but that makes the idea of un-associating it even better, since unlike changing the associativity, it actually makes the problem obvious and easy to fix. Alternatively, of course, we could make a tool that detects this and alerts the user, but making it loud still sounds better. And the breakage we are discussing is not trivial - it's a logic change which makes code silently take different codepath without anybody knowing. In the world of BC breaks, this is one of the most evil ones. So we should avoid it as much as possible. Rather than simply pointing to a 3-year-old close-reason, it would be prudent to actually get statistics on how often this unexpected behavior is relied upon in large, popular codebases. Packagist Github, that Usually the burden of proof lays on whoever proposes the change. Note that a lot of code is not public, especially for languages like PHP that is used for websites - meaning, there's little reason to publicize any code but reusable library code. And the fact that the change would not break a handful of popular libraries doesn't mean it won't break scores of websites whose source you can not see, but which are way more important for the people using them than some library they don't use. Yes, I understand that this means very high burden on somebody proposing BC-breaking change, and it makes the development more conservative. It is a high burden convince people that this change is worth the risk of breaking potentially unknown code with unknown consequences. I think, however, it's better than actually suffering these consequences. Consider that however ugly this particular wart is, people has been living with it for almost 20 years, and it may be preferable for them to have somewhat ugly code than having broken code. I don't think the we've been sick so long we're used to it now argument is very compelling. Some BC is expected in major revisions; and, historically, we have been WAY too conservative about that, in my view. When there's a major version and there's a BC-breaking change that either fixes something many people have been complaining about or improves the language in some other way without losing its identity, it should be a go. Major revisions are when changes like this are supposed to be made because, otherwise, these problems remain forever. I don't think it's rational to continue to ignore one of the most-requested fixes to PHP because one or two people out there may be relying on the broken behavior-- and yes, it is broken in the sense that it does not behave in the manner it's expected to for a C-like syntax. Didn't we talk about doing polls before? We should do a poll on this in the PHP community and see who, if anyone, has any code anywhere that relies on this confusingly counter-intuitive behavior. I would be amazed if even one person answered yes to that. So rather than continuing to guess and make unfounded assumptions, why don't we just ask them and settle the question here and now? --Kris It's short responses like this and the continued reliance on arguments posed in a different era/landscape that compel me to reconsider my continued participation in the PHP community at all. Sorry, but arguing from do this or that or I'm quitting does not seem a very strong argument to me. More drama does not help to evaluate the merits of changing the associativity of ?:. I think everybody here values the time of the volunteers that continue to contribute to the project, but I think keeping the discussion on the technical merits would be better. --
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 12/15/2014 2:11 PM, Stanislav Malyshev wrote: There's not that many breaking changes accepted, and each of them had to be substantiated. We had other breaking changes is not a substantiation. For example, most uses of associativity are wrong ones - is, but that makes the idea of un-associating it even better, since unlike changing the associativity, it actually makes the problem obvious and easy to fix. Alternatively, of course, we could make a tool that detects this and alerts the user, but making it loud still sounds better. And the breakage we are discussing is not trivial - it's a logic change which makes code silently take different codepath without anybody knowing. In the world of BC breaks, this is one of the most evil ones. So we should avoid it as much as possible. The justification for not making breaking changes always grows as a function amount-of-code-in-the-wild which could possibly be relying on bugs. This situation results in a permanent conclusion of 'better-never' in lieu of 'better-now-than-later'. In PHP-land, the implication then is that this gridlock cannot be resolved even by major versions (IMO, one of very few reasons for major versions to exist *at all*). Usually the burden of proof lays on whoever proposes the change. Note that a lot of code is not public, especially for languages like PHP that is used for websites - meaning, there's little reason to publicize any code but reusable library code. And the fact that the change would not break a handful of popular libraries doesn't mean it won't break scores of websites whose source you can not see, but which are way more important for the people using them than some library they don't use. Yes, I understand that this means very high burden on somebody proposing BC-breaking change, and it makes the development more conservative. It is a high burden convince people that this change is worth the risk of breaking potentially unknown code with unknown consequences. Without telemetry, there is obviously no way of *ever* asserting that something is ripe for removal or even deprecation. So this burden of proof is unmeetable by definition. -- Leon Sorokin -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 12/15/2014 11:59 AM, Robert Williams wrote:
What world is this that you live in where every line of code that’s written is
fully unit-tested
You took my example too literally; forget the unit tests. Imagine the
situation differently:
1. Someone wrote this function:
function add_five_pct($num) {
return $num * 1.10;
}
2. This function was then used to calculate profit margin and display
retail prices on your site and business has been great! Unknowingly,
you've been making 2x what was intended with no ill effects!
3. A new hire then went through this code on his own accord and decided,
'wait, this function is a bug!' and took it upon himself to fix it to
'$num * 1.05'.
Would you say the e-commerce site has been 'fixed' to work correctly?
Should the dev be praised for fixing the clearly broken function without
consulting anyone?
I cannot come up with a clearer explanation of how a 'silent' code fix
can foul up the bigger picture in non-beneficial ways. That's the
scenario that's being discussed here. The main point of contention is,
no one knows how much code exists in the wild that uses and relies on
this misbehavior. My argument is 'negligible', others say it's
'non-negligible'. And the whole comedy is, no one can actually provide
definitive numbers since nobody will ever know but a tiny portion of all
source code that is out there, so all arguments stem from 'meta'
evidence and personal experience.
--
Leon Sorokin
--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On Mon, Dec 15, 2014 at 8:19 PM, Leon Sorokin leeon...@gmail.com wrote:
On 12/15/2014 11:59 AM, Robert Williams wrote:
What world is this that you live in where every line of code that’s
written is fully unit-tested
You took my example too literally; forget the unit tests. Imagine the
situation differently:
1. Someone wrote this function:
function add_five_pct($num) {
return $num * 1.10;
}
2. This function was then used to calculate profit margin and display
retail prices on your site and business has been great! Unknowingly, you've
been making 2x what was intended with no ill effects!
3. A new hire then went through this code on his own accord and decided,
'wait, this function is a bug!' and took it upon himself to fix it to '$num
* 1.05'.
Would you say the e-commerce site has been 'fixed' to work correctly?
Should the dev be praised for fixing the clearly broken function without
consulting anyone?
I cannot come up with a clearer explanation of how a 'silent' code fix can
foul up the bigger picture in non-beneficial ways. That's the scenario
that's being discussed here. The main point of contention is, no one knows
how much code exists in the wild that uses and relies on this misbehavior.
My argument is 'negligible', others say it's 'non-negligible'. And the
whole comedy is, no one can actually provide definitive numbers since
nobody will ever know but a tiny portion of all source code that is out
there, so all arguments stem from 'meta' evidence and personal experience.
--
Leon Sorokin
--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php
Precisely why I suggested we do a poll and find out. Polling is a valid
means of getting a reasonable accounting of a particular metric. If we use
a sufficiently diverse and representative sample, we should easily be able
to get accurate enough results to settle this question once and for all.
The only cost is effort.
--Kris
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 12/14/2014 12:51 AM, Levi Morrison wrote: While I think long-term this would be a beneficial change I think in the short term it's quite a hurdle. This discussion will be identical whether we wait till PHP7 or PHP9 in a decade. The longer this change takes to make, the more code that will be mis-written to rely on the current behavior. If any long-term benefit is to be reaped, now is the best time to do it - every future major version will have a harder justification to make. There is definitely code out there relying on this behavior and changing it will result in the worst BC case: it will not fail in any way but will instead act differently. There are also definitely IE5.5 users out there and websites that rely on IE5.5-only features, but the actual numbers matter. There's no doubt that somebody, somewhere is going to have broken code because they wrote it without reading the docs that recommend against it or without understanding how it works, or upgraded without reading a migration guide or realizing that major version upgrades do make breaking changes (more often than not). These people do exist and they may curse PHP rather than themselves and leave it forever; the desire of the core team to retain the maximum amount of these users is puzzling. The change under discussion will not be causing any sort of mass-exodus from PHP, the ecosystem will not collapse and it will not be the heat-death of the universe. It will be removing a long-discouraged behavior and bring expected uniformity to a common construct that has differed for no good reason from other languages. There's plenty of room for a #5 on the already non-0 list: https://wiki.php.net/phpng#incompatibilities_made_on_purpose_and_are_not_going_to_be_fixed In my opinion, chaining or nesting ternaries at all should be discouraged; changing the associativity doesn't change the fact that they are more difficult to follow and more error prone than using different constructs. I would disagree on this point. Just like there are cases where a large switch/case results in more readable if-elseif chains, long conditional assignment chains can serve the same purpose, granted you space them appropriately. I would even go as far as saying that with proper spacing, they are more readable than the 'if' or 'case' blocks that would need to replace them. -- Leon Sorokin -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 14 December 2014 at 08:24, Leon Sorokin leeon...@gmail.com wrote: On 12/14/2014 12:51 AM, Levi Morrison wrote: While I think long-term this would be a beneficial change I think in the short term it's quite a hurdle. This discussion will be identical whether we wait till PHP7 or PHP9 in a decade. The longer this change takes to make, the more code that will be mis-written to rely on the current behavior. If any long-term benefit is to be reaped, now is the best time to do it - every future major version will have a harder justification to make. There is definitely code out there relying on this behavior and changing it will result in the worst BC case: it will not fail in any way but will instead act differently. There are also definitely IE5.5 users out there and websites that rely on IE5.5-only features, but the actual numbers matter. There's no doubt that somebody, somewhere is going to have broken code because they wrote it without reading the docs that recommend against it or without understanding how it works, or upgraded without reading a migration guide or realizing that major version upgrades do make breaking changes (more often than not). These people do exist and they may curse PHP rather than themselves and leave it forever; the desire of the core team to retain the maximum amount of these users is puzzling. The change under discussion will not be causing any sort of mass-exodus from PHP, the ecosystem will not collapse and it will not be the heat-death of the universe. It will be removing a long-discouraged behavior and bring expected uniformity to a common construct that has differed for no good reason from other languages. There's plenty of room for a #5 on the already non-0 list: https://wiki.php.net/phpng#incompatibilities_made_on_ purpose_and_are_not_going_to_be_fixed In my opinion, chaining or nesting ternaries at all should be discouraged; changing the associativity doesn't change the fact that they are more difficult to follow and more error prone than using different constructs. I would disagree on this point. Just like there are cases where a large switch/case results in more readable if-elseif chains, long conditional assignment chains can serve the same purpose, granted you space them appropriately. I would even go as far as saying that with proper spacing, they are more readable than the 'if' or 'case' blocks that would need to replace them. -- Leon Sorokin -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php If you wanted an upgrade path that was not Evil (in the sense of not introducing subtle and hard-to-diagnose bugs), could you not change the operator to be *un*associative in PHP7? That would effectively just make concrete the discouragement/deprecation that's already in the documentation, and would produce irritating but very visible errors for anyone still actually using this functionality, as well as making them alter their code in a forward-compatible way. Then if you want to think really long term, plan to implement the 'correct' associativity in the *next* major version. --G
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 14 Dec 2014, at 12:01, George Bond happy.melon.wiki...@gmail.com wrote: If you wanted an upgrade path that was not Evil (in the sense of not introducing subtle and hard-to-diagnose bugs), could you not change the operator to be *un*associative in PHP7? That would effectively just make concrete the discouragement/deprecation that's already in the documentation, and would produce irritating but very visible errors for anyone still actually using this functionality, as well as making them alter their code in a forward-compatible way. Then if you want to think really long term, plan to implement the 'correct' associativity in the *next* major version. Hey George, That sounds like a good approach, actually, although I'm not sure about later fixing the associativity. If we make it non-associative this does break things, but very loudly rather than changing code's behaviour. I think we should do this. Thanks. -- Andrea Faulds http://ajf.me/ -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
-Original Message- From: Andrea Faulds [mailto:a...@ajf.me] Sent: Sunday, December 14, 2014 2:26 PM To: George Bond Cc: PHP internals Subject: Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0? On 14 Dec 2014, at 12:01, George Bond happy.melon.wiki...@gmail.com wrote: If you wanted an upgrade path that was not Evil (in the sense of not introducing subtle and hard-to-diagnose bugs), could you not change the operator to be *un*associative in PHP7? That would effectively just make concrete the discouragement/deprecation that's already in the documentation, and would produce irritating but very visible errors for anyone still actually using this functionality, as well as making them alter their code in a forward-compatible way. Then if you want to think really long term, plan to implement the 'correct' associativity in the *next* major version. Hey George, That sounds like a good approach, actually, although I'm not sure about later fixing the associativity. If we make it non-associative this does break things, but very loudly rather than changing code's behaviour. I think we should do this. Although my inclination would be not to change anything, I agree that if we do decide to change it, George's idea is the best approach. Zeev -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
This sounds like a reasonable compromise to me and infinitely better than doing nothing. However, if 7.0 complains loudly enough about this already quasi-deprecated pattern, then the incubation period for an eventual fix need not be that of a decade-out major version, but of a 7.x point release. Oddly, 5.4 is a good example of a much larger incompatibility changelog than the provisional one for 7.0: http://php.net/manual/en/migration54.incompatible.php -- Leon Sorokin On 12/14/2014 6:01 AM, George Bond wrote: On 14 December 2014 at 08:24, Leon Sorokin leeon...@gmail.com wrote: On 12/14/2014 12:51 AM, Levi Morrison wrote: While I think long-term this would be a beneficial change I think in the short term it's quite a hurdle. This discussion will be identical whether we wait till PHP7 or PHP9 in a decade. The longer this change takes to make, the more code that will be mis-written to rely on the current behavior. If any long-term benefit is to be reaped, now is the best time to do it - every future major version will have a harder justification to make. There is definitely code out there relying on this behavior and changing it will result in the worst BC case: it will not fail in any way but will instead act differently. There are also definitely IE5.5 users out there and websites that rely on IE5.5-only features, but the actual numbers matter. There's no doubt that somebody, somewhere is going to have broken code because they wrote it without reading the docs that recommend against it or without understanding how it works, or upgraded without reading a migration guide or realizing that major version upgrades do make breaking changes (more often than not). These people do exist and they may curse PHP rather than themselves and leave it forever; the desire of the core team to retain the maximum amount of these users is puzzling. The change under discussion will not be causing any sort of mass-exodus from PHP, the ecosystem will not collapse and it will not be the heat-death of the universe. It will be removing a long-discouraged behavior and bring expected uniformity to a common construct that has differed for no good reason from other languages. There's plenty of room for a #5 on the already non-0 list: https://wiki.php.net/phpng#incompatibilities_made_on_ purpose_and_are_not_going_to_be_fixed In my opinion, chaining or nesting ternaries at all should be discouraged; changing the associativity doesn't change the fact that they are more difficult to follow and more error prone than using different constructs. I would disagree on this point. Just like there are cases where a large switch/case results in more readable if-elseif chains, long conditional assignment chains can serve the same purpose, granted you space them appropriately. I would even go as far as saying that with proper spacing, they are more readable than the 'if' or 'case' blocks that would need to replace them. -- Leon Sorokin -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php If you wanted an upgrade path that was not Evil (in the sense of not introducing subtle and hard-to-diagnose bugs), could you not change the operator to be *un*associative in PHP7? That would effectively just make concrete the discouragement/deprecation that's already in the documentation, and would produce irritating but very visible errors for anyone still actually using this functionality, as well as making them alter their code in a forward-compatible way. Then if you want to think really long term, plan to implement the 'correct' associativity in the *next* major version. --G -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 14 December 2014 17:31:52 GMT, Leon Sorokin leeon...@gmail.com wrote: This sounds like a reasonable compromise to me and infinitely better than doing nothing. However, if 7.0 complains loudly enough about this already quasi-deprecated pattern, then the incubation period for an eventual fix need not be that of a decade-out major version, but of a 7.x point release. Oddly, 5.4 is a good example of a much larger incompatibility changelog than the provisional one for 7.0: http://php.net/manual/en/migration54.incompatible.php 5.4 is a good example of what we *don't* want to do with minor versions. It consisted of a messy list of those bits of the abandoned 6 which didn't quite make it into 5.3. If we want major features more often, we can have major releases more often. This figure of 10 years gets mentioned a lot, but with annual releases, it wouldn't be unreasonable to expect 8.0 by 2020 (a year after 7.4). -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 14/12/14 19:48, Rowan Collins wrote: 5.4 is a good example of what we *don't* want to do with minor versions. It consisted of a messy list of those bits of the abandoned 6 which didn't quite make it into 5.3. 5.4 should have been '6' with a 5.4 that provided the very same buffer that 5.7 is now envisaged to provide with PHP7. There is still a substantial code base reliant on legacy features such as register_globals which requires substantial work to move from 5.3 to 5.4 and it is stumbling blocks like these which are STILL holding up adoption of later versions with ISP's. Anything 'broken' in PHP7 must have a managed upgrade path helped by warnings in 5.7, and I'd even go as far as to say that proposed patches for things like this fix should include migration tools before being merged! So both 5.7 and 7 are required to prevent a rerun of previous chaos ... -- Lester Caine - G8HFL - Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk Rainbow Digital Media - http://rainbowdigitalmedia.co.uk -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
Some thoughts from user land… On the concern of breaking code out there that relies on the current behavior, I strongly suspect far more code would be *fixed* if the ternary operator were changed to match what other languages do. I hate to admit it, but my own shop is a good example. We have a particular application that has thousands of business rules in the form of boolean expressions written using the ternary operator. When I took over the application, every one of them that was non-trivial (i.e., 95% of them) was wrong because the developers who wrote them didn’t understand how the operator works. It’s still a problem. If the operator were fixed in v7 — really fixed, not just made non-associative — all those rules would magically work; that alone would present a strong impetus for us to migrate that app. And the problem isn’t restricted to “those” guys that worked on that application back in the dark ages. The folks working here now still struggle with ternary if they haven’t used it recently. They’ve had enough code flagged in reviews to know that it’s problematic, but the usual solution is to rewrite it with switch or if-else, or to go crazy with parentheses. Either way, their code won’t break if the operator is fixed. I’ve also interviewed a lot of PHP developers, and I usually ask about the ternary operator. Depending on their experience level, my hope is that they either A) know all about it and can use it without fear, but are respectful of the confusion it can cause others, or B) they don’t really understand it, but they know it can bite them so that they’re careful if they encounter it or feel the need to use it. The vast majority of the time, however, I get C) they think they know all about it and have no fear of using it — but their understanding is completely wrong. This is across the board, all experience levels from junior guys with a year under their belts to senior guys with 10+ years. So, it seems that very few PHP developers actually understand how the ternary operator works in PHP. And those that do, because they tend to rarely use it in nested form, usually either just avoid doing so even when it makes sense or uses parentheses to avoid having to think too hard. Either way, their code is probably safe, and even if it’s not, nested use of ternary is so rare in most code bases that a manual review is not too troublesome. As for the vast majority of developers who don’t understand the operator: the code everyone here is so worried about breaking is largely written by these folks, and *it’s already broken*. Fixing the ternary operator now will only help most of this code, while making it non-associative will break the code in a different way while also breaking the code of those who do understand the operator. Fixing it now, or changing it now to fix it later - either way, working code that doesn’t rely on parentheses needs to be adjusted. Fortunately, the nested ternary is a rare beast (in most apps, anyway), but even so, most folks would like to do that review only once. And if it’s to adjust code to work more sanely, the way most other languages do it, well, it stings a lot less in that case. So my opinion, as a manager of millions of lines of closed-source code that I know no one else will fix for me, is to make changes to the ternary operator just once, and make that change one that fixes it to fit most people’s expectations. That’s the path that would be most beneficial to me. -- Bob Williams SVP, Software Development Newtek Business Services, Inc. “The Small Business Authority” http://www.thesba.com/ Notice: This communication, including attachments, may contain information that is confidential. It constitutes non-public information intended to be conveyed only to the designated recipient(s). If the reader or recipient of this communication is not the intended recipient, an employee or agent of the intended recipient who is responsible for delivering it to the intended recipient, or if you believe that you have received this communication in error, please notify the sender immediately by return e-mail and promptly delete this e-mail, including attachments without reading or saving them in any manner. The unauthorized use, dissemination, distribution, or reproduction of this e-mail, including attachments, is prohibited and may be unlawful. If you have received this email in error, please notify us immediately by e-mail or telephone and delete the e-mail and the attachments (if any).
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 12/14/2014 10:45 PM, Robert Williams wrote: I strongly suspect far more code would be *fixed* if the ternary operator were changed to match what other languages do. I appreciate your support, but either I am not understanding you, or your reasoning is unsound. If you have 'incorrectly' functioning code today that results in passing unit tests and a correctly functioning business. Then a sudden change to the behavior of this code would necessarily result in failing unit tests and an incorrectly functioning business. The code may be 'fixed' from a semantic point of view, but the logic would be broken from a required-output point of view relative to how it was operating previously, regardless of whether it was understood or not when it was written. -- Leon Sorokin -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
[PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
Hi guys, I was wondering if 7.0 could be the version to fix the long-standing incorrect ternary associativity bug in PHP [1]. This seems especially worthy of reconsideration since the Null Coalesce RFC has been accepted and merged [2] with the correct associativity [3]. The major version change seems like the only time to get this done in PHP. [1] https://bugs.php.net/bug.php?id=61915 [2] https://wiki.php.net/rfc/isset_ternary [3] http://news.php.net/php.internals/79584 thanks, -- Leon Sorokin -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
Hey Leon, On 13 Dec 2014, at 22:45, Leon Sorokin leeon...@gmail.com wrote: I was wondering if 7.0 could be the version to fix the long-standing incorrect ternary associativity bug in PHP [1]. This seems especially worthy of reconsideration since the Null Coalesce RFC has been accepted and merged [2] with the correct associativity [3]. The major version change seems like the only time to get this done in PHP. I’d love to see this fixed. I would be surprised if any code relies on the current behaviour and doesn’t just use brackets, since it’s so unintuitive. Thanks. -- Andrea Faulds http://ajf.me/ -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On Sat, 13 Dec 2014, Leon Sorokin wrote: I was wondering if 7.0 could be the version to fix the long-standing incorrect ternary associativity bug in PHP [1]. It is not a bug, as the issue's status says: Not a bug. This seems especially worthy of reconsideration since the Null Coalesce RFC has been accepted and merged [2] with the correct associativity [3]. It's another one of those bonkers changes. It changes behaviour of already existing syntax. This sort of meddling with the language is difficult to detect, and there is little value in fixing it. Don't piss off users for purety. I suggest you read this too: http://derickrethans.nl/bc-dont-be-evil.html The major version change seems like the only time to get this done in PHP. Only time it is *allowed*; that doesn't it should be done. cheers, Derick -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
I wonder how many people use ternary operators in an associative context. My suspicion is that little of those that do really intend PHP associativity. But it'd need quite a parser to detect the affected usage. -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
Respectfully, PHP's 'Unexpected behavior is not a bug' stance is pretty infuriating; the utterly ridiculous T_PAAMAYIM_NEKUDOTAYIM argument comes to mind. It is not a bug, as the issue's status says: Not a bug. I can understand why this would have been a 'wontfix' for versions pre-7.0. However, major version changes are done primarily to fix these kinds of inconsistencies - that and marketing - and yes they are precisely that: bugs. Documentation of unexpected behavior does not make something 'not a bug'. I and countless other PHP devs simply avoid using these easily correctable, useful language features because they are cumbersome, unexpected and actively discouraged in the documentation itself; how the sum of these facts doesn't qualify as a bug is outside all but the narrowest, most bizarre definitions of 'bug' that exists in any software community. The fact that it *may* break *some* code that is used somewhere despite documentation recommending against it (pretty much deprecating it already for years) is a terrible reason not to re-evaluate the situation given the huge opportunity to correct this. It's another one of those bonkers changes. It changes behaviour of already existing syntax. This sort of meddling with the language is difficult to detect, and there is little value in fixing it. Don't piss off users for purety. The only thing that's bonkers here is outright refusal to make trivially breaking changes (in addition to numerous other breaking changes already accepted) simply for the sake of not breaking some 0.1% of outdated, against-recommendation code. This is not an argument for purity - I want a working-as-expected ternary syntax as a feature, right now it is an un-feature and is a caveat that must be documented - it is a wart. If the goal was purity, PHP wouldn't even make the list of languages I would consider. Rather than simply pointing to a 3-year-old close-reason, it would be prudent to actually get statistics on how often this unexpected behavior is relied upon in large, popular codebases. Packagist Github, that didnt exist significantly in the PHP community in 2012, would be a good place to start. It would not even be outside the realm of possibility to do a bit of evangelism via Github issues if such cases are found so they can be fixed with a 1-year notice. It's short responses like this and the continued reliance on arguments posed in a different era/landscape that compel me to reconsider my continued participation in the PHP community at all. cheers, -- Leon Sorokin On 12/13/2014 5:20 PM, Derick Rethans wrote: On Sat, 13 Dec 2014, Leon Sorokin wrote: I was wondering if 7.0 could be the version to fix the long-standing incorrect ternary associativity bug in PHP [1]. It is not a bug, as the issue's status says: Not a bug. This seems especially worthy of reconsideration since the Null Coalesce RFC has been accepted and merged [2] with the correct associativity [3]. It's another one of those bonkers changes. It changes behaviour of already existing syntax. This sort of meddling with the language is difficult to detect, and there is little value in fixing it. Don't piss off users for purety. I suggest you read this too: http://derickrethans.nl/bc-dont-be-evil.html The major version change seems like the only time to get this done in PHP. Only time it is *allowed*; that doesn't it should be done. cheers, Derick -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On Sat, Dec 13, 2014 at 4:53 PM, Leon Sorokin leeon...@gmail.com wrote: Respectfully, PHP's 'Unexpected behavior is not a bug' stance is pretty infuriating; the utterly ridiculous T_PAAMAYIM_NEKUDOTAYIM argument comes to mind. It is not a bug, as the issue's status says: Not a bug. I can understand why this would have been a 'wontfix' for versions pre-7.0. However, major version changes are done primarily to fix these kinds of inconsistencies - that and marketing - and yes they are precisely that: bugs. Documentation of unexpected behavior does not make something 'not a bug'. I and countless other PHP devs simply avoid using these easily correctable, useful language features because they are cumbersome, unexpected and actively discouraged in the documentation itself; how the sum of these facts doesn't qualify as a bug is outside all but the narrowest, most bizarre definitions of 'bug' that exists in any software community. The fact that it *may* break *some* code that is used somewhere despite documentation recommending against it (pretty much deprecating it already for years) is a terrible reason not to re-evaluate the situation given the huge opportunity to correct this. It's another one of those bonkers changes. It changes behaviour of already existing syntax. This sort of meddling with the language is difficult to detect, and there is little value in fixing it. Don't piss off users for purety. The only thing that's bonkers here is outright refusal to make trivially breaking changes (in addition to numerous other breaking changes already accepted) simply for the sake of not breaking some 0.1% of outdated, against-recommendation code. This is not an argument for purity - I want a working-as-expected ternary syntax as a feature, right now it is an un-feature and is a caveat that must be documented - it is a wart. If the goal was purity, PHP wouldn't even make the list of languages I would consider. Rather than simply pointing to a 3-year-old close-reason, it would be prudent to actually get statistics on how often this unexpected behavior is relied upon in large, popular codebases. Packagist Github, that didnt exist significantly in the PHP community in 2012, would be a good place to start. It would not even be outside the realm of possibility to do a bit of evangelism via Github issues if such cases are found so they can be fixed with a 1-year notice. It's short responses like this and the continued reliance on arguments posed in a different era/landscape that compel me to reconsider my continued participation in the PHP community at all. cheers, -- Leon Sorokin On 12/13/2014 5:20 PM, Derick Rethans wrote: On Sat, 13 Dec 2014, Leon Sorokin wrote: I was wondering if 7.0 could be the version to fix the long-standing incorrect ternary associativity bug in PHP [1]. It is not a bug, as the issue's status says: Not a bug. This seems especially worthy of reconsideration since the Null Coalesce RFC has been accepted and merged [2] with the correct associativity [3]. It's another one of those bonkers changes. It changes behaviour of already existing syntax. This sort of meddling with the language is difficult to detect, and there is little value in fixing it. Don't piss off users for purety. I suggest you read this too: http://derickrethans.nl/bc-dont-be-evil.html The major version change seems like the only time to get this done in PHP. Only time it is *allowed*; that doesn't it should be done. cheers, Derick -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php Ok I'm going to draft an RFC for this when I have a spare moment. This is exactly the sort of contentious issue that the RFC process was created to help resolve. We'll bring it to a vote and everyone will make their arguments. If 2/3 vote to change the behavior, that'll be that. I respect Derrick's position on this but I could not disagree with it more. --Kris
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
On 14/12/2014 00:53, Leon Sorokin wrote: Respectfully, PHP's 'Unexpected behavior is not a bug' stance is pretty infuriating [...] Documentation of unexpected behavior does not make something 'not a bug'. Whether or not this particular bug is fixable, I do agree with this: we're not going to fix this because it's hard / too late is not the same as this is not a bug. For instance, attempting to decrement a null value with the -- operator results in null, even though incrementing with ++ will result in int(1), and, even more bafflingly, using -= 1 will result in int(-1). This is documented behaviour, but with no rationale other than it's always been that way. http://3v4l.org/bfsZ8 Apparently, this bug has been around since (at least) PHP 3, but does that really mean we're never allowed to fix it? At least the resolution to this report was Won't Fix rather than Not a Bug: https://bugs.php.net/bug.php?id=20548 Personally, I consider the non-evaluation of arguments to undeclared constructors (see Default constructors RFC thread) to be another example (an unfortunate consequence of a valid optimisation, resulting in behaviour that nobody would have specified), although Stas disagrees. As I mentioned in that other thread, one of the implications of saying it's not a bug is to assert that it's part of the *language* to work a particular way, and so should be specified and reproduced in other implementations (from tests on 3v4l.org, HHVM carefully replicates the null-- bug, but not the no-constructor lazy evaluation). Changing it then implies changing the language specification, and other implementations matching the appropriate version. If, on the other hand, we accept certain things as *bugs in the implementation*, then other implementations may diverge in behaviour anyway, and a new major version released on php.net could (in a sort of philosophical way) be considered a new implementation. Now, the associativity of the ternary operator is presumably in the language specification already, and belongs there, as it's such a basic attribute of the operator. I'm also inclined to agree that the benefit may not outweigh the cost of fixing it at this stage, but I do think it's worth discussing. -- Rowan Collins [IMSoP] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] Fix incorrect ternary '?' associativity for 7.0?
While I think long-term this would be a beneficial change I think in the short term it's quite a hurdle. There is definitely code out there relying on this behavior and changing it will result in the worst BC case: it will not fail in any way but will instead act differently. I definitely want to clean up the language, but I don't see the value in this one. In my opinion, chaining or nesting ternaries at all should be discouraged; changing the associativity doesn't change the fact that they are more difficult to follow and more error prone than using different constructs. -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
