Fwd: [tmql-wg] TMQL Issue: Functions and Predicates as first-class topics

[Lars Heuer]

[...]
>>> What about allowing this in CTM:
>>>
>>>   person rho
>>>      shoesize 43
>>>
>>> which is saying
>>>
>>>   rho isa person
>>>   shoesize: 43
>>
>> I'll leave it to the other Lars to tell us whether that's workable  
>> or not in CTM.

The problem is, that we need a delimiter somewhere because the scope
is not delimited explictely.

   Current CTM:

   rho isa person
   homepage: http://www.... @au office
   shoesize: 43

If we want to eliminate the colon, we could write

   rho isa person
   homepage http://www.... @(au office)
   shoesize 43

which I find less readable than the version with the colon. And in
Leipzig the committee decided that CTM with colons is more readable
than a version without. We presentent a version without the colons,
but it was not welcomed.

[...]
>>> or dropping the tmql: prefix
>>>
>>>    def nr_employees
>>>        return fn:length ( $o <- employer)
>>>
>>> would also be a valid topic syntax.
>>
>> This looks a lot nicer. What about parameter declaration? What  
>> about multi-line functions?

For the template syntax in CTM we use

    ctm:tpl identifier
            [... template content ...]
    end

for templates which have only one paramter. If the template should
take more than one parameter, the user must use brackets.

     ctm:tpl identifier($param, $param)
            [... template content ...]
     end


(The user can also use brackets for just one parameter but she is not
forced to do so).

A bit Ruby-alike.

We use a namespace instead of a keyword but I am open minded to change
that.

Best regards,
Lars
-- 
http://www.semagia.com