Re: [O] [babel] Some variables with no default value don't provoke an error

[Eric Schulte]

Hi,

"Sebastien Vauban" <address@hidden> writes:

> Hi Eric,
>
> Eric Schulte wrote:
>> "Sebastien Vauban" <address@hidden> writes:
>>> Weirdly enough, in the following code block, I must add a default value for
>>> vars `table', `column' and `type' but not for the var `nullability'.
>>>
>>> I've even been able to add fake vars `something' and `else' with no error
>>> being reported (at ingestion time):
>>>
>>> #+srcname: add-column-in-table(table="", column="", something, type="", 
>>> else, nullability)
>>> #+begin_src sql
>>> -- add column `$column' (if column does not exist yet)
>>> IF NOT EXISTS (SELECT *
>>>                FROM INFORMATION_SCHEMA.COLUMNS
>>>                WHERE TABLE_NAME = '$table'
>>>                AND COLUMN_NAME = '$column')
>>> BEGIN
>>>     ALTER TABLE $table
>>>     ADD $column $type $nullability
>>> END
>>> #+end_src
>>>
>>> Note that, in the above state, the code block is ingested with no error, 
>>> but,
>>> if I remove the default value of var `table', it then generates back an
>>> error...
>>
>> I've just pushed up a check for these functional-syntax variables which
>> will ensure that each is given a default value.  Since this check takes
>> place at the location of the code block it /does/ include the name of
>> the code block in the error message.
>
> If you have a couple of minutes, can you clarify some points to be sure I can
> understand:
>
> - What do you call functional-syntax vars?  The ones in the #+srcname, next to
>   the block name, as opposed to the ones declared as :var arguments?
>

yes, that's exactly it, I don't know what "functional-syntax" is a good
or descriptive term, but it is used in the source code so I'm now
repeating it.

>
>   The fact, then, that we can get a clearer message in case of error, seems to
>   me an incentive to use that type of declaration...
>

I personally prefer the traditional ":var" style, I'll have to add
similar error checking there...

>
> - Why was `nullability' not detected to have no default value?  Why were
>   `table', `column' and `type' well correctly detected?
>

Meaning after you assigned values to the first three no error was thrown
when the fourth (nullability) wasn't assigned a value?  Could you
provide a minimal example?

>
> Best regards,
>   Seb

-- 
Eric Schulte
http://cs.unm.edu/~eschulte/