====== PHP RFC: Allow int type argument to BCMath function ======
  * Version: 0.9
  * Date: 2024-07-08
  * Author: Saki Takamachi (saki@php.net)
  * Status: Under Discussion 
  * First Published at: https://wiki.php.net/rfc/allow_int_args_to_bcmath_function

===== Introduction =====
Currently, BCMath functions only accept values ​​as strings. If want to calculate an int type with BCMath, need to convert it to a string once, which incurs unnecessary conversion costs. 

===== Proposal =====
This RFC proposes adding an int type to the BCMath function argument and making the argument a union type of int and string.

That is, the function signature changes to:

<PHP>
function bcadd(int|string $num1, int|string $num2, ?int $scale = null): string {}

function bcsub(int|string $num1, int|string $num2, ?int $scale = null): string {}

function bcmul(int|string $num1, int|string $num2, ?int $scale = null): string {}

function bcdiv(int|string $num1, int|string $num2, ?int $scale = null): string {}

function bcmod(int|string $num1, int|string $num2, ?int $scale = null): string {}

function bcpowmod(int|string $num, int|string $exponent, int|string $modulus, ?int $scale = null): string {}

function bcpow(int|string $num, int|string $exponent, ?int $scale = null): string {}

function bcsqrt(int|string $num, ?int $scale = null): string {}

function bccomp(int|string $num1, int|string $num2, ?int $scale = null): int {}

function bcround(int|string $num, int $precision = 0, int $mode = PHP_ROUND_HALF_UP): string {}
</PHP>

Note that even if the only numbers passed as arguments are ints, the return value will always be a string.

I do not change anything for the following three functions. <php>bcscale()</php> is not a calculation function, so exclude it. <php>bcfloor()</php> and <php>bcceil()</php> are excluded because there is no point in allowing int type arguments due to the characteristics of their functions.

<PHP>
function bcscale(?int $scale = null): int {}

function bcfloor(string $num): string {}

function bcceil(string $num): string {}
</PHP>

===== Backward Incompatible Changes =====
Any code that uses strict types and expects an error to occur when passing an int to these functions is affected because the error no longer occurs.

===== Proposed PHP Version(s) =====
next PHP 8.x (8.4)

===== RFC Impact =====
==== To SAPIs ====
None.

==== To Existing Extensions ====
Only BCMath.

==== To Opcache ====
None.

==== New Constants ====
None.

==== php.ini Defaults ====
None.

===== Open Issues =====
None.

===== Unaffected PHP Functionality =====
There is no effect on anything other than BCMath.

===== Future Scope =====
None.

===== Proposed Voting Choices =====
There is a yes/no choice whether to accept this RFC and requires a 2/3 majority vote to be accepted.

===== Patches and Tests =====
yet

===== Implementation =====
yet

===== References =====
https://externals.io/message/123924

===== Rejected Features =====
None.