[jsdl-wg] Issues for the teleconference tomorrow

[Karl Czajkowski]

On Mar 08, Andreas Savva loaded a tape reading:
> Karl, Michel
> 
> Karl Czajkowski wrote:
> >On Mar 07, Michel Drescher loaded a tape reading:
> >
> >
> >>1) Argument list handling in jsdl:Application
> >>Basically, the modeling of command line arguments in a whole string is 
> >>... cumbersome? I know, it works, but it looks ugly.
> 
> Michel, I think the word you were looking for was 'simple.' ;-)
> 

It is "simple" right up until you need to pass through strings that
have your separator whitespace, or quote marks, or what have you
embedded in one program argument!  I think it is much simpler to
maintain structured data than it is to try to embed funny
serializations of structured data into the JSDL info set model.  This
is particularly so when a consumer of this document needs to translate
the structure into some arbitrarily different structure or serialized
syntax to safely pass it through local implementation layers.

That was certainly our experience in trying to make GRAM RSL sane... I
often regretted the fact that we didn't use as much explicit
parenthetic grouping for arguments as we did for environment
variables, because users often made bad assumptions about where the
argument strings were separated versus treated as one string that
needed to be "reparsed".  Our (pre-WS) RSL parser explicitly
represented a sequence of strings in the right-hand side of the
"arguments" clause parse, and we had a somewhat standard whitespace,
quoting, and quote-escape mechanism to allow people to express any
possible argument list.

For example:

  (arguments= foo bar   baz   )

was a shorthand for:

  (arguments="foo" "bar" "baz")

and you could get whitespace or a stray quote in with:

  (arguments="foo bar" "baz""spliced")

which would render as this in the current proposal:

  <arguments>
    <argument>foo bar</argument>
    <argument>baz"spliced</argument>
  </arguments>

which I certainly think is more obvious than the RSL way. :-)

I suppose the only tricky one now would be getting angle brackets in
there:

    <argument>&lt;not a tag&gt;</argument>


karl

-- 
Karl Czajkowski
karlcz at univa.com