Re: def app = apply, problem

From: pjb@xxxxxxxxxxxxxxxxx (Pascal J. Bourguignon)
Date: Tue, 29 Apr 2008 19:39:25 +0200

globalrev <skanemupp@xxxxxxxx> writes:

instead of:
CL-USER> (apply #'+ '(1 2 3))
6

i want to do:
(app + (1 2 3))

(def app (oper expr)
(apply #'oper 'expr))

doesnt work though, i get
CL-USER> (app + (3 4)) 3 is not a function name

(app + '(3 4))
FUNCTION: undefined function OPER
[Condition of type SYSTEM::SIMPLE-UNDEFINED-FUNCTION]

(app + (3 4)) gives 3 not a function name if:
(def app (oper expr)
(funcall #'oper expr))

What is def?

(defmacro app (operator arguments) `(,operator ,@arguments))

But then you cannot do the equivalent of:

(let ((op (if (oddp (random 2)) '+ '-)))
(apply op '(29 3)))

(let ((op (if (oddp (random 2)) '+ '-)))
(app op (29 3))) ; breaks.

and on the other hand, if you already know the operator and arguments (app + (1 2 3))
why not just write: (+ 1 2 3) ?

--
__Pascal Bourguignon__
.

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References:
- def app = apply, problem
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Re: def app = apply, problem
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def app = apply, problem
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Re: def app = apply, problem
... FUNCTION: undefined function OPER ... (def app (oper expr) ...
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