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# 31jan08abu
# (c) Software Lab. Alexander Burger
# 'setf' is the most perverse concept ever introduced into Lisp
(de setf "Args"
(let "P" (car "Args")
(set
(if (atom "P")
"P"
(let (: :: get prop car prog cadr cdr caddr cadr cadddr caddr)
(eval "P") ) )
(eval (cadr "Args")) ) ) )
### Test ###
(test 7
(use A
(setf A 7)
A ) )
(test (7 2 3)
(let L (1 2 3)
(setf (car L) 7)
L ) )
(test (1 7 3)
(let L (1 2 3)
(setf (cadr L) 7)
L ) )
(test 7
(put 'A 'a 1)
(setf (get 'A 'a) 7)
(get 'A 'a) )
(test 7
(put 'A 'a 1)
(with 'A
(setf (: a) 7)
(: a) ) )
# But also:
(undef 'foo)
(de foo (X)
(cadr X) )
(test (1 7 3)
(let L (1 2 3) (setf (foo L) 7) L) )
# vi:et:ts=3:sw=3
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