Re: patch: to_string, to_array functions

2010/7/21 Robert Haas <robertmhaas@gmail.com>:
> On Wed, Jul 21, 2010 at 1:48 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
>> 2010/7/21 Robert Haas <robertmhaas@gmail.com>:
>>> On Wed, Jul 21, 2010 at 12:08 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
>>>>>> I am thinking so we have to do decision about string_to_array and
>>>>>> array_to_string deprecation first. If these function will be
>>>>>> deprecated, then we can use a similar names (and probably we should to
>>>>>> use a similar names) - so text_to_array or array_to_string can be
>>>>>> acceptable. If not, then this discus is needless - then to_string and
>>>>>> to_array have to be maximally in contrib - stringfunc is good idea -
>>>>>> and maybe we don't need thinking about new names.
>>>>>
>>>>> Well, -1 from me for deprecating string_to_array and array_to_string.
>>>>>
>>>>> I am not in favor of the names to_string and to_array even if we put
>>>>> them in contrib, though.  The problem with string_to_array and
>>>>> array_to_string is that they aren't descriptive enough, and
>>>>> to_string/to_array is even less so.
>>>>
>>>> I am not a English native speaker, so I have a different feeling.
>>>> These functions do array_serialisation and array_deseralisation, but
>>>> this names are too long. I have not idea about better names - it is
>>>> descriptive well (for me) text->array, array->text - and these names
>>>> shows very cleanly symmetry between functions. I have to repeat - it
>>>> is very clean for not native speaker.
>>>
>>> Well, the problem is that array_to_string(), for example, tells you
>>> that an array is being converted to a string, but not how.  And
>>> to_string() tells you that you're getting a string, but it doesn't
>>> tell you either what you're getting it from or how you're getting it.
>>> We already have a function to_char() which can be used to format a
>>> whole bunch of different types as strings; I can't see adding a new
>>> function with almost the same name that does something completely
>>> different.
>>>
>>> array_split() and array_join(), following Perl?  array_implode() and
>>> array_explode(), along the lines suggested by Brendan?
>>
>> I have a problem with array_split - because there string is split. I
>> looked on net - and languages usually uses a "split" or "join". split
>> is method of str class in Java. So when I am following Perl, I feel
>> better with  just only "split" and "join", but "join" is keyword :( -
>> step back, maybe string_split X array_join ?
>>
>> select string_split('1,2,3,4',',');
>> select array_join(array[1,2,3,4],',');
>>
>> so my preferences:
>>
>> 1. split, join - I checked - we are able to create "join" function
>> 2. split, array_join - when only "join" can be a problem
>> 3. string_split, array_join - there are not clean symmetry, but it
>> respect wide used a semantics - string.split, array.join
>> 4. explode, implode
>> 5. array_explode, array_implode
>> -- I cannot to like array_split - it is contradiction for me.
>
> Well, I guess I prefer my suggestion to any of those (I know... what a
> surprise), but I think I could live with #3, #4, or #5.  It's hard for
> me to imagine that we really want to create a function called just
> join(), given the other meanings that JOIN already has in SQL.

it hasn't any relation to SQL language - but I don't expect so some
like this can be accepted by Tom :). So for this moment we are in
agreement on #3, #4, #5. I think, we can wait one or two days for
opinions of others - and than I'll fix patch. ok?

Regards
Pavel


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> Robert Haas
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