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Postings from March 2022
>
>
> 2022-3-14 21:51 Arne Johannessen <aj22@thaw.de> wrote:
>
>> Yuki Kimoto wrote:
>> >
>> > My understanding:
>> >
>> > Perl 5.36+ can detect a string and a number completely.
>> >
>> > a string - SvPOK
>> > a number - (SvIOK or SvNOK) and not SvPOK
>>
>> No, I think Perl has always been able to do this. Deep down, it is
>> currently implemented like this:
>>
>> is a string - SVp_POK
>> is a number - SVp_IOK or SVp_NOK
>>
>> Note that scalars can be, and indeed often are, strings and numbers at
>> the same time. The new feature in 5.36 is that Perl can now also detect if
>> a value /started/ as a string or number, which is important to know in some
>> rare use cases:
>>
>> created as string - SVf_POK
>> created as number - (SVf_IOK or SVf_NOK) and not SVf_POK
>>
>>
>
>
I can't understand the word "started"(and "created") not yet.
This is because I don't know the cases that the value is changed after
"started".
A value is started as a number (3). If the value is used as a string, "3"
is maybe cached to the pv slot.
A value is started as a string ("3"). If the value is used as a number, 3
is maybe cached to the nv or iv slot.
As Darren says, Is the value classified to a string or a number from the
starting to the destruction, not only starting?
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