LISP-likeness
A number of features of AppleScript seem to suggest that someone on the original AppleScript team was fond of LISP (or some LISP dialect such as Scheme). Since I, too, am fond of Scheme, I rather like these features.
For example, AppleScript has lists, which are ordered collections of
any values whatever. It provides certain primitive operations for
dealing these lists, such as taking the first element, taking
everything but the first element, and joining two lists into one
(like Scheme’s car
,
cdr
, and cons
). And AppleScript
permits recursion
(a subroutine calling itself).
Thus, it is possible to write AppleScript code that bears an
extraordinary resemblance to Scheme code. To give an example,
here’s a little Scheme program that defines a
routine for removing the n
th element from
a list, and then tests it:
(define remvix (lambda (ix ls) (cond ((null? ls) '( )) ((= ix 1) (cdr ls)) (else (cons (car ls) (remvix (- ix 1) (cdr ls))))))) (remvix 2 '(mannie moe jack))
And here’s the same thing done in just the same style in AppleScript:
on remvix(ix, ls) if ls is {} then return {} else if ix is 1 then return rest of ls else return {item 1 of ls} & remvix(ix - 1, rest of ls) end if end remvix remvix(2, {"Mannie", "Moe", "Jack"})
Even if you don’t know any Scheme or any AppleScript, the structural and stylistic similarity between these approaches is hard to miss; they are in fact move for move identical, the only differences between them being matters of syntactic detail. To be ...
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