Re: DTB: Problem/Erratum for DTBin function string-join

this is fine with me

On Tue, 15 Sep 2009 17:14:58 +0100
Axel Polleres <axel.polleres@deri.org> wrote:

> Michael,
> 
> we discussed that in the phone conference...
> and the general opinion was to keep with the
> easy fix I proposed unless you object.
> Do you?
> 
> Thanks,
> Axel
> 
> 
> On 17 Aug 2009, at 21:52, Michael Kifer wrote:
> 
> > i think using lists is a cleaner solution in general
> >
> > On Mon, 17 Aug 2009 21:28:27 +0100
> > Axel Polleres <axel.polleres@deri.org> wrote:
> >
> > > Hi all,
> > >
> > > While working on the all-builtins use case, I realize a slight
> > > error/problem in DTB now with the function:
> > >
> > > func:string-join(...)
> > >
> > > its xpath/xquery counterpart fn:string-join(...)
> > >
> > > takes two arguments:
> > > - a sequence of strings
> > > - a "separator" string
> > >
> > > now I realize - since this function was introduced when we didn't  
> > heva
> > > lists in RIF yet, that we seem to have expected a "flattened" list  
> > as
> > > input, i.e. we give the schemas
> > >
> > > ( ?arg1 ?arg2; func:string-join(?arg1 ?arg2 ) )
> > >
> > > ( ?arg1 ?arg2 ?arg3; func:string-join(?arg1 ?arg2 ?arg3 ) )
> > >
> > > ...
> > >
> > > ( ?arg1  ?arg2 ... ?argn; func:string-join(?arg1 ?arg2 ... ?argn ) )
> > >
> > >
> > > Anyways, the semantics is defined in terms of fn:string-join, which
> > > didn't work so far, but only works with a small fix, i.e.  
> > interpreting
> > > the first n-1 arguments as the sequence argument of the CPAth/Xquery
> > > fn:string-join function. "Historically" this is IMO what we meant,  
> > as
> > > there was no lists.
> > >
> > > Thus, I see two options for fixing this:
> > >
> > > a) stick with the flattened version, interpreting the first n-1
> > > arguments as the sequence argument of the CPAth/Xquery fn:string- 
> > join
> > > function and the last argument as the separator string.
> > >
> > > b) make the function with a fixed arity of 2,  the domain of the  
> > first
> > > argument being a list of strings and the second argument the  
> > separator
> > > string.
> > >
> > > I implemented option a) now, since it is the "least intrusive"  
> > change to
> > > the current doc, see
> > >
> > > http://www.w3.org/2005/rules/wiki/index.php?title=DTB&diff=10665&oldid=10495
> > >
> > > however, b) seems somehow the more natural way to proceed. The
> > > disadvantage/worry I see with b) is that we might want to implement
> > > "emulating" sequences by lists as input in other functions as  
> > well...
> > > Opinions?
> > >
> > > Axel
> > >
> > >
> > >
> >
>

Received on Wednesday, 16 September 2009 08:20:51 UTC