On Fri, Jul 28, 2023 at 4:04 PM Kamil Ziemian <kziemian...@gmail.com> wrote:
> Hello,
>
> After a long break, I go back to reading Go Spec.
>
> In the section "Expression statements" we read that "The following
> built-in functions are not permitted in statement context:
>
> append cap complex imag len make new real
> unsafe.Add unsafe.Alignof unsafe.Offsetof unsafe.Sizeof unsafe.Slice
>
> h(x+y)
> f.Close()
> <-ch
> (<-ch)
> len("foo") // illegal if len is the built-in function"
>
> Are things following "h(x+y)" also forbidden in the statement context?
> This part of spec isn't specially clear in my opinion.
>
No, they are not. Otherwise, they'd have a comment following them saying
"illegal for $reason".
>
> Best regards,
> Kamil
> poniedziałek, 12 czerwca 2023 o 02:02:27 UTC+2 Rob Pike napisał(a):
>
>> Although the sentence is OK as it stands, the section should be tweaked a
>> bit. One of the examples there (myString(0x65e5)) is valid Go but vet
>> rejects it, as part of the move towards disallowing this conversion, which
>> was there mostly for bootstrapping the libraries.
>>
>> -rob
>>
>>
>> On Mon, Jun 12, 2023 at 3:10 AM 'Axel Wagner' via golang-nuts <
>> golan...@googlegroups.com> wrote:
>>
>>> Ah, the spec does actually say:
>>>>
>>>> Converting a signed or unsigned integer value to a string type yields a
>>>> string containing the UTF-8 representation of the integer. Values outside
>>>> the range of valid Unicode code points are converted to "\uFFFD".
>>>
>>>
>>> Personally, I think this is fine as is. I think people understand what
>>> happens from these two sentences.
>>>
>>> On Sun, Jun 11, 2023 at 7:02 PM Axel Wagner <axel.wa...@googlemail.com>
>>> wrote:
>>>
>>>> I'm not entirely sure. I don't think your phrasing is correct, as it
>>>> doesn't represent what happens if the integer value exceeds the range of
>>>> valid codepoints (i.e. if it needs more than 32 bits to represent). That
>>>> being said, the sentence as is also isn't really precise about it. From
>>>> what I can tell, the result is not valid UTF-8 in any case.
>>>>
>>>> I think it might make sense to file an issue about this, though in
>>>> general that conversion is deprecated anyway and gets flagged by `go vet`
>>>> (and `go test`) because it is not what's usually expected. So I'm not sure
>>>> how important it is to get this exactly right and understandable.
>>>>
>>>>
>>>> On Sun, Jun 11, 2023 at 5:17 PM Kamil Ziemian <kziem...@gmail.com>
>>>> wrote:
>>>>
>>>>> I have some hair splitting question. In the "Conversions to and from a
>>>>> string type" we read:
>>>>> "Converting a signed or unsigned integer value to a string type yields
>>>>> a string containing the UTF-8 representation of the integer."
>>>>>
>>>>> Would it be more corrected to say, that conversion from integer to
>>>>> string gives you UTF-8 representation of code point described by value of
>>>>> the integer? Or maybe it is indeed representation of integer described by
>>>>> UTF-8 specification?
>>>>>
>>>>> Best regards,
>>>>> Kamil
>>>>> czwartek, 28 października 2021 o 19:33:27 UTC+2 Kamil Ziemian
>>>>> napisał(a):
>>>>>
>>>>>> Hello,
>>>>>>
>>>>>> From what I understand proper Gopher read at least one time "The Go
>>>>>> Programming Language Specification" (https://golang.org/ref/spec)
>>>>>> and now I need to read it too.
>>>>>>
>>>>>> I learn something of Extended Backus-Naur Form to understand it, so
>>>>>> if I say something stupid beyond belief, I hope you will forgive me. In
>>>>>> the
>>>>>> first part "Notation" (https://golang.org/ref/spec#Notation) I
>>>>>> believe that I understand meaning of all concepts except of
>>>>>> "production_name". On one hand "production_name" means that it is name of
>>>>>> the production, not rocket science here. On the other, after reading
>>>>>> about
>>>>>> EBNF I feel that I should have more information about it. Can you explain
>>>>>> it to me?
>>>>>>
>>>>>> Again I'm new to EBNF, so maybe this is stupid question.
>>>>>>
>>>>>> Best
>>>>>> Kamil
>>>>>>
>>>>>> --
>>>>> You received this message because you are subscribed to the Google
>>>>> Groups "golang-nuts" group.
>>>>> To unsubscribe from this group and stop receiving emails from it, send
>>>>> an email to golang-nuts...@googlegroups.com.
>>>>> To view this discussion on the web visit
>>>>> https://groups.google.com/d/msgid/golang-nuts/06347585-fd2c-4bfa-9527-3439389c6414n%40googlegroups.com
>>>>> <https://groups.google.com/d/msgid/golang-nuts/06347585-fd2c-4bfa-9527-3439389c6414n%40googlegroups.com?utm_medium=email&utm_source=footer>
>>>>> .
>>>>>
>>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "golang-nuts" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to golang-nuts...@googlegroups.com.
>>>
>> To view this discussion on the web visit
>>> https://groups.google.com/d/msgid/golang-nuts/CAEkBMfHaG8bYNLvLERu0-ad57wpoWsiB%2BFC5asyKA7FH6%2BvgZw%40mail.gmail.com
>>> <https://groups.google.com/d/msgid/golang-nuts/CAEkBMfHaG8bYNLvLERu0-ad57wpoWsiB%2BFC5asyKA7FH6%2BvgZw%40mail.gmail.com?utm_medium=email&utm_source=footer>
>>> .
>>>
>> --
> You received this message because you are subscribed to the Google Groups
> "golang-nuts" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to golang-nuts+unsubscr...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/golang-nuts/a2031526-c215-4594-8da3-2aea38d95d85n%40googlegroups.com
> <https://groups.google.com/d/msgid/golang-nuts/a2031526-c215-4594-8da3-2aea38d95d85n%40googlegroups.com?utm_medium=email&utm_source=footer>
> .
>
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/golang-nuts/CAEkBMfEqQLQSCKW19AaKYTnr-Ek3CPHKgs2hdAuxBu_HVs_etQ%40mail.gmail.com.
