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Re: A Franz Lisp question.
In article <660@shuldig.Huji.Ac.IL> firstname.lastname@example.org writes:
>As you all might well know, Franz Lisp is a dynamic binding langauge, while
>Scheme is not. Therefore, the following code is unwriteable in Franz Lisp:
>(define (func param)
> (lambda (x) (param x)))
>[This function accepts a parameter which is also a function, and returns yet
>another function which 'apply's param on x.]
In Opus 38.92, you would write this:
(declare (special param))
(defun func (param)
#'(lambda (x) (funcall param x))))
"funcall" is used to call a functional object. "fclosure" is
used to make a closure over dynamic (ie, special) variables.
Hence "param" must be declared special if you want your code
to compile correctly.
The problem with compilation occurs because Franz is not a totally
dynamic binding language. It is for interpreted code, but in compiled
code variables have lexical scope (but only dynamic extent) by default.