Re: Scheme help...

[Paul Prescod <papresco@xxxxxxxxxxxxxxxx>]

I can tell you miss Perl from the amount of line-noise you add to your DSSSL 
scripts. :)

Anyhow, the question is about the difference between this:

(define foo (bar))
and
(define (foo) (bar))

I don't have my Perl book with me, but they are roughly analogous to:

foo = bar()

and 

foo =  function (){ # no args
    return bar();
}

Okay, that's not really Perl at all. The important thing to note is that 
this syntax:

(define (foo) (bar)) is just a syntactic shortcut for

(define foo (lambda () (bar)))

Where lambda is the special form that creates a new procedure in Scheme.

The effect on current-node may be clear already. The non-lambda definition
tries to execute (bar) immediately, at definition time, and the lambda-based
definition tries to execute (bar) later, at the point where (foo) is actually
executed.

 Paul Prescod


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