Re: [go-nuts] why iota can't be assigned to variables?

[roger peppe]

On 4 May 2017 at 03:52, T L  wrote:
>
>
> On Thursday, May 4, 2017 at 1:21:52 AM UTC+8, Axel Wagner wrote:
>>
>> On Wed, May 3, 2017 at 7:04 PM, T L  wrote:
>>>
>>>
>>>
>>> On Thursday, May 4, 2017 at 12:46:47 AM UTC+8, Axel Wagner wrote:

 but
 const (
 a = iota
 b
 s string
 d
 )
 is not a valid declaration. You can't say "the rule is the same for
 constants".
>>>
>>>
>>> For the same rule, I mean just copying the corresponding part from last
>>> line.
>>> Yes, declared constant must be assigned. This is an unrelated rule for
>>> this topic.
>>
>>
>> No, it is not an unrelated rule. Because it means that "just like for
>> consts" isn't an argument. You need, at the very least, answer the valid
>> question ("what happens with that var-declaration and why?") raised about
>> your proposal. Or better yet, realize that var and const declarations behave
>> very differently and thus "consistency" isn't an argument to add something
>> otherwise useless.
>>
>
> ok, I admit the rule difference between variable and constant declaration
> does matter:
>
> var (
> a int = iota
> b// should autocomplete
> c int// but this? "c int" is already legal.
> )

I don't think I've ever come across a case where I want to assign
increasing-by-one values to adjacent variables. Have you?

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Re: [go-nuts] why iota can't be assigned to variables?

[T L]

On Thursday, May 4, 2017 at 1:21:52 AM UTC+8, Axel Wagner wrote:
>
> On Wed, May 3, 2017 at 7:04 PM, T L  
> wrote:
>
>>
>>
>> On Thursday, May 4, 2017 at 12:46:47 AM UTC+8, Axel Wagner wrote:
>>>
>>> but
>>> const (
>>> a = iota
>>> b
>>> s string
>>> d
>>> )
>>> is not a valid declaration. You can't say "the rule is the same for 
>>> constants".
>>>
>>
>> For the same rule, I mean just copying the corresponding part from last 
>> line.
>> Yes, declared constant must be assigned. This is an unrelated rule for 
>> this topic.
>>
>
> No, it is not an unrelated rule. Because it means that "just like for 
> consts" isn't an argument. You need, at the very least, answer the valid 
> question ("what happens with that var-declaration and why?") raised about 
> your proposal. Or better yet, realize that var and const declarations 
> behave very differently and thus "consistency" isn't an argument to add 
> something otherwise useless.
>
>
ok, I admit the rule difference between variable and constant declaration 
does matter:

var (
a int = iota
b// should autocomplete
c int// but this? "c int" is already legal.
)

 

>
>>  
>>
>>>
>>> Again: const-declarations and variable declarations are very different. 
>>> You can not argue "it's the same"; it's not.
>>>
>>> On Wed, May 3, 2017 at 6:28 PM, T L  wrote:
>>>


 On Thursday, May 4, 2017 at 12:17:13 AM UTC+8, Jan Mercl wrote:
>
> On Wed, May 3, 2017 at 6:00 PM T L  wrote:
>
> > Just like what expected for constants.
>
> For constants it's expected to reuse the last iota expression when 
> absent. Do you propose that
>
> var (
> a = iota
> b
> )
>
> will become valid and initialize a to 0 and b to 1?
>
> If so, is it valid and what shall happen when one writes
>
> var (
> a = iota
> b
> s string
> d
> )
>
> ?
>

 The rule is same for constants: d is also string, as s.

  

>
> If it's not valid, why?
>
>
> -- 
>
> -j
>
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>>>
>>> -- 
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>>
>
>

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Re: [go-nuts] why iota can't be assigned to variables?

['Axel Wagner' via golang-nuts]

On Wed, May 3, 2017 at 7:04 PM, T L  wrote:

>
>
> On Thursday, May 4, 2017 at 12:46:47 AM UTC+8, Axel Wagner wrote:
>>
>> but
>> const (
>> a = iota
>> b
>> s string
>> d
>> )
>> is not a valid declaration. You can't say "the rule is the same for
>> constants".
>>
>
> For the same rule, I mean just copying the corresponding part from last
> line.
> Yes, declared constant must be assigned. This is an unrelated rule for
> this topic.
>

No, it is not an unrelated rule. Because it means that "just like for
consts" isn't an argument. You need, at the very least, answer the valid
question ("what happens with that var-declaration and why?") raised about
your proposal. Or better yet, realize that var and const declarations
behave very differently and thus "consistency" isn't an argument to add
something otherwise useless.


>
>
>>
>> Again: const-declarations and variable declarations are very different.
>> You can not argue "it's the same"; it's not.
>>
>> On Wed, May 3, 2017 at 6:28 PM, T L  wrote:
>>
>>>
>>>
>>> On Thursday, May 4, 2017 at 12:17:13 AM UTC+8, Jan Mercl wrote:

 On Wed, May 3, 2017 at 6:00 PM T L  wrote:

 > Just like what expected for constants.

 For constants it's expected to reuse the last iota expression when
 absent. Do you propose that

 var (
 a = iota
 b
 )

 will become valid and initialize a to 0 and b to 1?

 If so, is it valid and what shall happen when one writes

 var (
 a = iota
 b
 s string
 d
 )

 ?

>>>
>>> The rule is same for constants: d is also string, as s.
>>>
>>>
>>>

 If it's not valid, why?


 --

 -j

>>> --
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>>
>> --
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Re: [go-nuts] why iota can't be assigned to variables?

[T L]

On Thursday, May 4, 2017 at 12:46:47 AM UTC+8, Axel Wagner wrote:
>
> but
> const (
> a = iota
> b
> s string
> d
> )
> is not a valid declaration. You can't say "the rule is the same for 
> constants".
>

For the same rule, I mean just copying the corresponding part from last 
line.
Yes, declared constant must be assigned. This is an unrelated rule for this 
topic.

 

>
> Again: const-declarations and variable declarations are very different. 
> You can not argue "it's the same"; it's not.
>
> On Wed, May 3, 2017 at 6:28 PM, T L  
> wrote:
>
>>
>>
>> On Thursday, May 4, 2017 at 12:17:13 AM UTC+8, Jan Mercl wrote:
>>>
>>> On Wed, May 3, 2017 at 6:00 PM T L  wrote:
>>>
>>> > Just like what expected for constants.
>>>
>>> For constants it's expected to reuse the last iota expression when 
>>> absent. Do you propose that
>>>
>>> var (
>>> a = iota
>>> b
>>> )
>>>
>>> will become valid and initialize a to 0 and b to 1?
>>>
>>> If so, is it valid and what shall happen when one writes
>>>
>>> var (
>>> a = iota
>>> b
>>> s string
>>> d
>>> )
>>>
>>> ?
>>>
>>
>> The rule is same for constants: d is also string, as s.
>>
>>  
>>
>>>
>>> If it's not valid, why?
>>>
>>>
>>> -- 
>>>
>>> -j
>>>
>> -- 
>> 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 .
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>>
>
>

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Re: [go-nuts] why iota can't be assigned to variables?

['Axel Wagner' via golang-nuts]

but
const (
a = iota
b
s string
d
)
is not a valid declaration. You can't say "the rule is the same for
constants".

Again: const-declarations and variable declarations are very different. You
can not argue "it's the same"; it's not.

On Wed, May 3, 2017 at 6:28 PM, T L  wrote:

>
>
> On Thursday, May 4, 2017 at 12:17:13 AM UTC+8, Jan Mercl wrote:
>>
>> On Wed, May 3, 2017 at 6:00 PM T L  wrote:
>>
>> > Just like what expected for constants.
>>
>> For constants it's expected to reuse the last iota expression when
>> absent. Do you propose that
>>
>> var (
>> a = iota
>> b
>> )
>>
>> will become valid and initialize a to 0 and b to 1?
>>
>> If so, is it valid and what shall happen when one writes
>>
>> var (
>> a = iota
>> b
>> s string
>> d
>> )
>>
>> ?
>>
>
> The rule is same for constants: d is also string, as s.
>
>
>
>>
>> If it's not valid, why?
>>
>>
>> --
>>
>> -j
>>
> --
> 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.
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>

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Re: [go-nuts] why iota can't be assigned to variables?

[T L]

On Thursday, May 4, 2017 at 12:17:13 AM UTC+8, Jan Mercl wrote:
>
> On Wed, May 3, 2017 at 6:00 PM T L  
> wrote:
>
> > Just like what expected for constants.
>
> For constants it's expected to reuse the last iota expression when absent. 
> Do you propose that
>
> var (
> a = iota
> b
> )
>
> will become valid and initialize a to 0 and b to 1?
>
> If so, is it valid and what shall happen when one writes
>
> var (
> a = iota
> b
> s string
> d
> )
>
> ?
>

The rule is same for constants: d is also string, as s.

 

>
> If it's not valid, why?
>
>
> -- 
>
> -j
>

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Re: [go-nuts] why iota can't be assigned to variables?

[Jan Mercl]

On Wed, May 3, 2017 at 6:00 PM T L  wrote:

> Just like what expected for constants.

For constants it's expected to reuse the last iota expression when absent.
Do you propose that

var (
a = iota
b
)

will become valid and initialize a to 0 and b to 1?

If so, is it valid and what shall happen when one writes

var (
a = iota
b
s string
d
)

?

If it's not valid, why?


-- 

-j

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Re: [go-nuts] why iota can't be assigned to variables?

[T L]

On Wednesday, May 3, 2017 at 11:39:29 PM UTC+8, Jan Mercl wrote:
>
> On Wed, May 3, 2017 at 5:07 PM T L  
> wrote:
>
> > The complexity is the same as iota in constant declarations. 
>
> How can that be claimed when still nobody ever seen any specification of 
> what var foo = iota shall do at all? The space of possible semantics is 
> unbounded. The sane subspace seems to me to be of zero volume, but will you 
> please just explain what you expect from assigning iota to a variable?
>

Just like what expected for constants.

var (
  a = iota // a == 0
  b = iota // b == 1
)
 

>
> Don't suppose telepathy exists, thank you ;-)
>
> -- 
>
> -j
>

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Re: [go-nuts] why iota can't be assigned to variables?

[Jan Mercl]

On Wed, May 3, 2017 at 5:07 PM T L  wrote:

> The complexity is the same as iota in constant declarations.

How can that be claimed when still nobody ever seen any specification of
what var foo = iota shall do at all? The space of possible semantics is
unbounded. The sane subspace seems to me to be of zero volume, but will you
please just explain what you expect from assigning iota to a variable?

Don't suppose telepathy exists, thank you ;-)

-- 

-j

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Re: [go-nuts] why iota can't be assigned to variables?

[Ayan George]

On 05/03/2017 10:38 AM, T L wrote:
> 
> 
> On Wednesday, May 3, 2017 at 9:28:28 PM UTC+8, Jan Mercl wrote:
> 
> On Wed, May 3, 2017 at 3:19 PM T L  
> wrote:
> 
> Why would you want to assign iota to a variable? What value should 
> iota in such case have?
> 
> 
> The request is not essential, but any harm of it?
> 

Can you show an example (some preferably some mocked up Go code) of how
this can be useful?

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Re: [go-nuts] why iota can't be assigned to variables?

[T L]

On Wednesday, May 3, 2017 at 10:53:42 PM UTC+8, Jan Mercl wrote:
>
> On Wed, May 3, 2017 at 4:38 PM T L  
> wrote:
>
> > The request is not essential, but any harm of it?
>
> How can anybody know that if nobody knows what it shall actually do and 
> what will be the impact on the complexity of the specification and 
> implementation?
>

The complexity is the same as iota in constant declarations. 


> -- 
>
> -j
>

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Re: [go-nuts] why iota can't be assigned to variables?

[Jan Mercl]

On Wed, May 3, 2017 at 4:38 PM T L  wrote:

> The request is not essential, but any harm of it?

How can anybody know that if nobody knows what it shall actually do and
what will be the impact on the complexity of the specification and
implementation?

-- 

-j

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Re: [go-nuts] why iota can't be assigned to variables?

[T L]

On Wednesday, May 3, 2017 at 9:28:28 PM UTC+8, Jan Mercl wrote:
>
> On Wed, May 3, 2017 at 3:19 PM T L  
> wrote:
>
> Why would you want to assign iota to a variable? What value should iota in 
> such case have?
>
>
The request is not essential, but any harm of it?
 

>
> -- 
>
> -j
>

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Re: [go-nuts] why iota can't be assigned to variables?

[Jan Mercl]

On Wed, May 3, 2017 at 3:19 PM T L  wrote:

Why would you want to assign iota to a variable? What value should iota in
such case have?


-- 

-j

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