Re: [xsl] [XPath 3.0] Why should I bother specifying the "arity" of a function that I invoke?

[Michael Kay <mike@xxxxxxxxxxxx>]

On 31/10/2012 21:06, Costello, Roger L. wrote:
> Hi Folks,
>
> The XPath 3.0 specification says that when a named function is invoked you should specify the number of arguments (i.e., the arity):
>
> 	NamedFunctionRef 	   ::=    	EQName "#" IntegerLiteral
>
> Here is an example:
>
>     	concat#3('Section', ': ', 1)
>
> But this works just as well:
>
> 	concat('Section', ': ', 1)
>
> So why should I bother specifying the arity? Is there a case where I *must* specify the arity?
concat#3 is an expression that returns a function item. You need it if 
you are going to store the function item in a variable, pass it to 
another function, return it from a function, or do other things that you 
can do with run-time values.

You don't need a run-time function item if you know statically what 
function to call and if the only thing you want to do is to call the 
function.

Michael Kay
Saxonica