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Date: Tue, 26 Aug 2025 14:36:05 -0500
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Subject: Re: [PHP-DEV] [RFC] Add "is_representable_as_float()" and
 "is_representable_as_int()" functions
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From: larry@garfieldtech.com ("Larry Garfield")

On Tue, Aug 26, 2025, at 1:36 PM, Tim D=C3=BCsterhus wrote:
> Hi
>
> On 8/26/25 16:48, Larry Garfield wrote:
>> I have multiple times just recently had need of "I have a numeric str=
ing, should I cast it to an int or a float?", for which an is_representa=
ble_as_int() function (or similar) would be quite helpful, and neater th=
an the messy solution I usually use.
>
> It would've been nice to know what that use-case is, rather than just=20
> knowing that you had that use-case.
>
> I'm having a hard time thinking of something where I don't a-priori kn=
ow=20
> what type I expect to get and would need to inspect the value to make =
a=20
> decision.
>
> I see how having a function that safely coerces a string into an int,=20
> returning null if coercion fails, basically intval() with better error=20
> handling and taking only `string`s, could be useful, but that's not wh=
at=20
> is being asked here.
>
> Best regards
> Tim D=C3=BCsterhus

When doing generic serialization, the input is often always-strings (eg,=
 environment variables, HTTP Query parameters, etc.)  When doing generic=
 code (not type generics, but "works on anything" kind of generic), I of=
ten have to resort to this:

https://github.com/Crell/EnvMapper/blob/master/src/EnvMapper.php#L88

Which gets the job done, but feels ugly to me.

Even if I know what the target type is, I still need to ask the question=
 "so does this string match the target type?" =20

https://github.com/Crell/Carica/blob/master/src/Middleware/NormalizeArgu=
mentTypesMiddleware.php#L73

"I have a string, the parameter wants an int, is that even possible?"  B=
eing able to replace that floor() nonsense with is_integerable() (by wha=
tever name) would make my life a lot easier.

For float, is_numeric() is already sufficient for my purposes.  I just n=
eed to be able to differentiate between "3" and "3.14" to cast to the co=
rrect type.

--Larry Garfield