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Re: A Conclusion Re: SchemeQL

MJ Ray wrote:

> I must say that I'm amazed.  I think I've just seen my first post ever
> where Shriram is posting something I vehemently and violently disagree
> with.  

Hmm, I'm losing my edge.  Must be old age. (-:

>	 Expecting templates to be written in scheme is totally
> wrong-headed.  The designers just won't go for it.  

Oh, but the templates are only barely written in Scheme.  As Noel
points out, they're largely written in a simplified XML syntax.  Think 
of it as a two-colored syntax, where (lacking color) upper-case
represents one color and lower-case another:

  (define (template TITLE)
    `(html
       (head
         (title ,TITLE))
       (body
         "Some body text")))

This is almost the same as writing

  (define (template TITLE)
    <html>
      <head>
        <title>TITLE</title>
      </head>
      <body>
         Some body text
      </body>
    </head>
  )

So let's make this sweeter:

  <define name="template" args="TITLE">
    <html>
      <head>
        <title>TITLE</title>
      </head>
      <body>
         Some body text
      </body>
    </head>
  </define>

Think of this as "HTML generation by example": you provide most of the 
code, leave a few parameters free, and fill in the parameters when you 
know them.

We've written a reader that converts rudimentary Scheme of this form
into actual Scheme that you can run.  That is, plug in the new reader, 
and you can actually run the above program.

>						      Mostly you get
> HTML from them, or XSLT if you're very lucky.  You will never get that
> sort of mark-up from them, because they have no tools to develop it.

Depends.  My development tool is all of DrScheme.  What's yours? (-:

(You might want to write John Clements, <clements@cs.rice.edu>, and
ask him for our "little languages" paper.  The code in it doesn't run
any longer with the version changes, but if someone's interested ...)

Shriram