Re: [PHP-DEV] Supporting object types in BCMath
Hi Jordan, > I've done a lot of performance tuning on my arbitrary precision library, and > will simply state for everyone here that I think the amount of development > effort involved in improving performance of the BCMath library is almost > certainly going to see a return on your effort that is not worth it. There > have been discussions over the last year on possibly working on bundling a > new arbitrary precision C library and providing something that is performant > enough to be generally useful in core, but that's not even at the RFC stage, > just investigations. > > I wouldn't say that improving BCMath is a waste of time, but there is also > probably lower hanging fruit once you get past things like Saki has here. > DevEx improvements. BCMath is slow, but currently no other extension can replace it in terms of computational accuracy. Therefore, I would like to advance these proposals with the aim of improving usability rather than improving performance. Since we have already completed the implementation of the important processes when creating the prototype, we will start preparing the RFC. Regards. Saki
Re: [PHP-DEV] Supporting object types in BCMath
On Sun, Mar 17, 2024 at 5:05 PM Saki Takamachi wrote: > Hi Jordan, > > > Using a BCNum inside a loop is the use case, where every loop would > result in memory allocation for a new object, as well as the overhead of > the constructor, etc. > > > > Granted, only people who REALLY know what they are doing should be doing > this. Though my library which essentially IS a wrapped for BCMath that is > upgradeable if you install other extensions (like ext-decimal) does support > both, I suggest using primarily immutables in my docs. > > > > That said, the C library itself for BCMath is insanely inefficient as > far as arbitrary precision math goes, so I would suggest that people don't > get their hopes up too much on the performance front. > > I just sent an email, and you're right about performance. Therefore, the > point of this proposal seems to be simply to improve convenience. > > Regards. > > Saki I've done a lot of performance tuning on my arbitrary precision library, and will simply state for everyone here that I think the amount of development effort involved in improving performance of the BCMath library is almost certainly going to see a return on your effort that is not worth it. There have been discussions over the last year on possibly working on bundling a new arbitrary precision C library and providing something that is performant enough to be generally useful in core, but that's not even at the RFC stage, just investigations. I wouldn't say that improving BCMath is a waste of time, but there is also probably lower hanging fruit once you get past things like Saki has here. DevEx improvements. Jordan
Re: [PHP-DEV] Supporting object types in BCMath
Hi Jordan, > Using a BCNum inside a loop is the use case, where every loop would result in > memory allocation for a new object, as well as the overhead of the > constructor, etc. > > Granted, only people who REALLY know what they are doing should be doing > this. Though my library which essentially IS a wrapped for BCMath that is > upgradeable if you install other extensions (like ext-decimal) does support > both, I suggest using primarily immutables in my docs. > > That said, the C library itself for BCMath is insanely inefficient as far as > arbitrary precision math goes, so I would suggest that people don't get their > hopes up too much on the performance front. I just sent an email, and you're right about performance. Therefore, the point of this proposal seems to be simply to improve convenience. Regards. Saki
Re: [PHP-DEV] Supporting object types in BCMath
Hi, I created a prototype, although it's pretty rough. It can overload operators and calculate not only between `BcNum` but also between `BcNum` and `int` or `string`. https://github.com/php/php-src/pull/13741 I compared the execution times. Test code: ```
Re: [PHP-DEV] Supporting object types in BCMath
On Sat, Mar 16, 2024 at 8:39 AM Saki Takamachi wrote: > Hi Barney, > > Thanks, that's what I was starting to worry about too. It seems like a > good idea to support only immutability, as you say earlier in your proposal. > > Regards. > > Saki Using a BCNum inside a loop is the use case, where every loop would result in memory allocation for a new object, as well as the overhead of the constructor, etc. Granted, only people who REALLY know what they are doing should be doing this. Though my library which essentially IS a wrapped for BCMath that is upgradeable if you install other extensions (like ext-decimal) does support both, I suggest using primarily immutables in my docs. That said, the C library itself for BCMath is insanely inefficient as far as arbitrary precision math goes, so I would suggest that people don't get their hopes up too much on the performance front. Jordan
Re: [PHP-DEV] Supporting object types in BCMath
Hi Barney, > I would suggest if you do this only supporting immutable objects, or at least > making immutable the default, the one with with the simpler name, and > reserving the mutable version specifically for when people want to use > mutability. The strings used with bcmath today are effectively immutable. > > It's hard to see why a number should be mutable though. Users of the class > can always wrap an immutable up it in a mutable object if they want. > > If you do have both mutable and immutable it might be worth giving the > methods separate names to make the distinction clearer - e.g. "add" for > mutable, "plus" for immutable, and maybe making the add method return void. Thanks, that's what I was starting to worry about too. It seems like a good idea to support only immutability, as you say earlier in your proposal. Regards. Saki
Re: [PHP-DEV] Supporting object types in BCMath
On 16/03/2024 05:22, Saki Takamachi wrote:
Yet another idea is to also support immutable objects, like DateTime.
e.g.
```
$num1 = new BcNum('1.235');
$num1imm = new BcNumImmutable('1.235');
$num2 = new BcNum('2.001');
$num1result = $num1->add($num2);
$num1immResult = $num1imm->add($num2);
I would suggest if you do this only supporting immutable objects, or at
least making immutable the default, the one with with the simpler name,
and reserving the mutable version specifically for when people want to
use mutability. The strings used with bcmath today are effectively
immutable.
It's hard to see why a number should be mutable though. Users of the
class can always wrap an immutable up it in a mutable object if they want.
If you do have both mutable and immutable it might be worth giving the
methods separate names to make the distinction clearer - e.g. "add" for
mutable, "plus" for immutable, and maybe making the add method return void.
[PHP-DEV] Supporting object types in BCMath
Hi internals,
BCMath currently only has procedural functions. This is a bit unwieldy for some
design patterns and I came up with the idea of supporting object types like
mysqli.
Yet another idea is to also support immutable objects, like DateTime.
e.g.
```
$num1 = new BcNum('1.235');
$num1imm = new BcNumImmutable('1.235');
$num2 = new BcNum('2.001');
$num1result = $num1->add($num2);
$num1immResult = $num1imm->add($num2);
$num1->getValue(); // '3.236'
$num1result->getValue(); // '3.236'
$num1imm->getValue(); // '1.235'
$num1immResult->getValue(); // '3.236'
```
The reason why the class name is not "BCNum" is because it needs to follow the
current PHP naming convention. As an example, the class name of a PDO subclass
has a name such as "PdoOdbc".
I look forward to your feedback.
Regards.
Saki
