# GMP object and is_scalar() - Thread: https://externals.io/message/70904 - Original archive: https://news-web.php.net/php.internals/70904 - Started by Yasuo Ohgaki on 2013-12-29T08:09:50+00:00 - Messages: 17 - Reply by email to internals@lists.php.net - More for agents: search with https://externals.io/search.md?q={query} · JSON API at https://externals.io/api · documentation at https://externals.io/llms.txt --- ## #70904 — Yasuo Ohgaki — 2013-12-29T08:09:50+00:00 URL: https://externals.io/message/70904#70904 Hi all, GMP object is object. Therefore, `is_scalar()` returns false for GMP objects. [yohgaki@dev php-src]$ ./php-bin -r '$v = gmp_init("0"); var_dump(gettype($v));' string(6) "object" [yohgaki@dev php-src]$ ./php-bin -r '$v = gmp_init("0"); var_dump(is_scalar($v));' bool(false) This is correct behavior, but this behavior is debatable, IMO. Any comments? -- Yasuo Ohgaki yohgaki@ohgaki.net --- ## #70905 — Yasuo Ohgaki — 2013-12-29T08:16:20+00:00 URL: https://externals.io/message/70904#70905 · In reply to: #70904 > GMP object is object. Therefore, `is_scalar()` returns false for GMP > objects. > > [yohgaki@dev php-src]$ ./php-bin -r '$v = gmp_init("0"); > var_dump(gettype($v));' > string(6) "object" > [yohgaki@dev php-src]$ ./php-bin -r '$v = gmp_init("0"); > var_dump(is_scalar($v));' > bool(false) > > This is correct behavior, but this behavior is debatable, IMO. > > Any comments? > `is_numeric()` can be problematic also. [yohgaki@dev php-src]$ ./php-bin -r '$v = gmp_init("0"); var_dump(is_numeric($v));' bool(false) -- Yasuo Ohgaki yohgaki@ohgaki.net --- ## #70907 — Nikita Popov — 2013-12-29T17:54:30+00:00 URL: https://externals.io/message/70904#70907 · In reply to: #70904 > Hi all, > > GMP object is object. Therefore, `is_scalar()` returns false for GMP > objects. > > [yohgaki@dev php-src]$ ./php-bin -r '$v = gmp_init("0"); > var_dump(gettype($v));' > string(6) "object" > [yohgaki@dev php-src]$ ./php-bin -r '$v = gmp_init("0"); > var_dump(is_scalar($v));' > bool(false) > > This is correct behavior, but this behavior is debatable, IMO. > > Any comments? > Sorry, I don't understand what you're saying. Why would is_scalar return true for an **object**? Nikita --- ## #70908 — Hannes Magnusson — 2013-12-29T19:26:26+00:00 URL: https://externals.io/message/70904#70908 · In reply to: #70907 > > > > […] > > Sorry, I don't understand what you're saying. Why would is_scalar return > true for an **object**? Its not even an object, its a resource. I think you are completely off path here Yasuo, same with your empty() thread. That just doesn't make sense. -Hannes --- ## #70909 — Hannes Magnusson — 2013-12-29T19:33:43+00:00 URL: https://externals.io/message/70904#70909 · In reply to: #70908 On Sun, Dec 29, 2013 at 11:26 AM, Hannes Magnusson wrote: > > > […] > > > Its not even an object, its a resource. > > I think you are completely off path here Yasuo, same with your empty() thread. > That just doesn't make sense. Waiiit a minute. It is a object in current master? That will break code that makes sure gmp_init() worked by doing `is_resource()` on the return value. -Hannes --- ## #70911 — Yasuo Ohgaki — 2013-12-29T22:12:22+00:00 URL: https://externals.io/message/70904#70911 · In reply to: #70907 Hi Nikita, > Sorry, I don't understand what you're saying. Why would is_scalar return > true for an **object**? Since GMP object works just like numbers, this could cause bug that users assume it is "number" or "scalar". Variables are promoted to GMP object when math operator is applied. (This is nice, IMO) GMP objects works like number mostly, this can be cause of bugs in user scripts. It would be more intuitive for users if GMP object is handled as "number" IMHO. Regards, -- Yasuo Ohgaki yohgaki@ohgaki.net --- ## #70927 — Stas Malyshev — 2013-12-30T20:45:58+00:00 URL: https://externals.io/message/70904#70927 · In reply to: #70911 Hi! > Since GMP object works just like numbers, this could cause bug that > users assume it is "number" or "scalar". is_scalar checks if the value is a scalar. Objects and resources are not scalars. If someone doesn't understand that, he should read manual page of is_scalar before using it. -- Stanislav Malyshev, Software Architect SugarCRM: http://www.sugarcrm.com/ (408)454-6900 ext. 227 --- ## #70930 — Yasuo Ohgaki — 2013-12-30T21:20:18+00:00 URL: https://externals.io/message/70904#70930 · In reply to: #70927 Hi Stas, On Tue, Dec 31, 2013 at 5:45 AM, Stas Malyshev wrote: > > […] > > is_scalar checks if the value is a scalar. Objects and resources are not > scalars. If someone doesn't understand that, he should read manual page > of is_scalar before using it. I agree. Generally speaking, users should know this. I'm bringing up this as issue to discuss, since GMP numbers will be work like numbers from PHP 5.6. Most users will expect numbers are evaluated like other numbers(int/float), I suppose. It may be hard to distinguish normal numbers(int/float) and GMP numbers in large scripts, too. I can think of 3 options for now. - Treat GMP object as special object - Make scalar object - Make autoboxing like feature We have 4th option that leave it as it now, but it wouldn't be user friendly. Since this (GMP numbers work like normal numbers) is new feature, we may choose better option. Regards, -- Yasuo Ohgaki yohgaki@ohgaki.net --- ## #70931 — Stas Malyshev — 2013-12-30T21:31:07+00:00 URL: https://externals.io/message/70904#70931 · In reply to: #70930 Hi! > Since this (GMP numbers work like normal numbers) is new feature, we > may choose better option. I think you're taking it way too far. GMP numbers may support some functions that scalars support, but that does not mean every function - especially functions with are *specifically designed* to distinguish scalars from objects - would do the same thing for them as for scalars. If you're interested in their "numeric" properties - i.e. adding them, multiplying them, etc. - fine, they work that way. But if you "pop the hood" and look inside - no, they should not be scalars inside, because they are not. -- Stanislav Malyshev, Software Architect SugarCRM: http://www.sugarcrm.com/ (408)454-6900 ext. 227 --- ## #70932 — Yasuo Ohgaki — 2013-12-30T21:35:57+00:00 URL: https://externals.io/message/70904#70932 · In reply to: #70931 Hi Stas, On Tue, Dec 31, 2013 at 6:31 AM, Stas Malyshev wrote: > > […] > > I think you're taking it way too far. GMP numbers may support some > functions that scalars support, but that does not mean every function - > especially functions with are *specifically designed* to distinguish > scalars from objects - would do the same thing for them as for scalars. > If you're interested in their "numeric" properties - i.e. adding them, > multiplying them, etc. - fine, they work that way. But if you "pop the > hood" and look inside - no, they should not be scalars inside, because > they are not. I agree with your opinion in general. How about to introduce scalar object that is evaluated as scalar? It would be useful in user land also. Regards, -- Yasuo Ohgaki yohgaki@ohgaki.net --- ## #70933 — Yasuo Ohgaki — 2013-12-30T21:46:07+00:00 URL: https://externals.io/message/70904#70933 · In reply to: #70932 Hi Stas, > On Tue, Dec 31, 2013 at 6:31 AM, Stas Malyshev wrote: > > > […] > > > I agree with your opinion in general. > > How about introduce scalar object that is evaluated as scalar? > It would be useful in user land also. > http://www.php.net/manual/en/language.oop5.magic.php Something like __toScalar(), may be? -- Yasuo Ohgaki yohgaki@ohgaki.net --- ## #70934 — Robert Stoll — 2013-12-30T21:55:53+00:00 URL: https://externals.io/message/70904#70934 · In reply to: #70933 > -----Original Message----- > From: yohgaki@gmail.com [mailto:yohgaki@gmail.com] On Behalf Of Yasuo Ohgaki > Sent: Monday, December 30, 2013 10:46 PM > To: Stas Malyshev > Cc: Nikita Popov; internals@lists.php.net > Subject: Re: [PHP-DEV] GMP object and `is_scalar()` > > Hi Stas, > > > > > […] > > http://www.php.net/manual/en/language.oop5.magic.php > > Something like __toScalar(), may be? > > -- > Yasuo Ohgaki > yohgaki@ohgaki.net I think __toScalar is way to wage, what will __toScalar() return? a bool, an int, a float or a string? --- ## #70935 — Yasuo Ohgaki — 2013-12-30T22:00:14+00:00 URL: https://externals.io/message/70904#70935 · In reply to: #70934 Hi Robert, > I think __toScalar is way to wage, what will __toScalar() return? a bool, > an int, a float or a string? Not all classes should have __toScalar(). Only classes that should be evaluated as scalar should implement this magic method. Return values are programmer's choice. Whatever scalar values may return. Regards, -- Yasuo Ohgaki yohgaki@ohgaki.net --- ## #70936 — Stas Malyshev — 2013-12-30T22:03:51+00:00 URL: https://externals.io/message/70904#70936 · In reply to: #70935 Hi! > Only classes that should be evaluated as scalar should implement this > magic method. We already have type convertors. "scalar" is not a type, it's a group of types. I don't think it makes sense to convert something to an abstract scalar - it should be specific scalar type. -- Stanislav Malyshev, Software Architect SugarCRM: http://www.sugarcrm.com/ (408)454-6900 ext. 227 --- ## #70937 — Yasuo Ohgaki — 2013-12-30T22:12:05+00:00 URL: https://externals.io/message/70904#70937 · In reply to: #70936 Hi Stas, On Tue, Dec 31, 2013 at 7:03 AM, Stas Malyshev wrote: > > […] > > We already have type convertors. "scalar" is not a type, it's a group of > types. I don't think it makes sense to convert something to an abstract > scalar - it should be specific scalar type. Should it? PHP is weakly typed language. I haven't thought well for scalar object yet and has to consider various cases. One thing clear to me is users expects GMP numbers behave like scalar numbers most likely. Yet another option for PHP 5.6 is to note GMP numbers as EXPERIMENTAL. There are many issues to resolve. IMHO. Regards, -- Yasuo Ohgaki yohgaki@ohgaki.net --- ## #70938 — Stas Malyshev — 2013-12-30T22:20:23+00:00 URL: https://externals.io/message/70904#70938 · In reply to: #70937 Hi! > Should it? PHP is weakly typed language. That doesn't mean types do not exist. That means values can be converted from type to type, but there's no type "scalar" - it is just a group name of a set of types. > One thing clear to me is users expects GMP numbers behave like > scalar numbers most likely. I don't think users expect anything like that, I don't see legitimate use case why users would expect is_scalar return true on GMP object. If the user is advanced enough to use is_scalar he should understand what that function does. Or user some other function that is more fit for their goals. > Yet another option for PHP 5.6 is to note GMP numbers as > EXPERIMENTAL. GMP is in PHP for a long time, why would it suddenly become experimental? -- Stanislav Malyshev, Software Architect SugarCRM: http://www.sugarcrm.com/ (408)454-6900 ext. 227 --- ## #70939 — Yasuo Ohgaki — 2013-12-30T22:49:51+00:00 URL: https://externals.io/message/70904#70939 · In reply to: #70938 Hi Stas, On Tue, Dec 31, 2013 at 7:20 AM, Stas Malyshev wrote: > > […] > > That doesn't mean types do not exist. That means values can be converted > from type to type, but there's no type "scalar" - it is just a group > name of a set of types. > Agreed on that scalar is name of types which has single value. > One thing clear to me is users expects GMP numbers behave like > > […] > > I don't think users expect anything like that, I don't see legitimate > use case why users would expect is_scalar return true on GMP object. If > the user is advanced enough to use is_scalar he should understand what > that function does. Or user some other function that is more fit for > their goals. > I agree users who know PHP and GMP well would not expect GMP object is to evaluated as scalar. I suppose average users would expect/want GMP number as PHP number also. > Yet another option for PHP 5.6 is to note GMP numbers as > > […] > > GMP is in PHP for a long time, why would it suddenly become experimental? Sorry, I meant GMP number arithmetic with normal operators/math functions/ type evaluation functions is better to be considered as EXPERIMENTAL. It lacks GMP float support and many function won't work as it should be. (If we consider GMP number as "number" in PHP) It's safe to note GMP number arithmetic as EXPERIMENTAL and resolve issues. IMHO. Regards, -- Yasuo Ohgaki yohgaki@ohgaki.net