Re: (apply #'and '(t t nil)) not work

f> Apparently and is not a normal function like +, -, ...
f> I can write (and t t nil), but if the parameters are packaged into a
f> list, how can I do?

indeed, AND is not a function, it's a special operator, pretty close to IF
or WHEN -- it stops evaluating as soon as it get first NIL (this is called
short circuiting sometimes).
there is a function called EVERY, it does exactly what you need:

CL-USER> (every #'identity '(t t nil))
NIL
CL-USER> (every #'identity '(t t t))
T

of course you can define your own function -- to get rid of #'indetity
parameter, or allowing it to agruments directly. i.e.

(defun my-and (&rest args) (every #'identity args))

CL-USER> (my-and t t nil)
NIL
CL-USER> (apply #'my-and '(t t nil))
NIL

this looks just like AND, but it does not short-circuit evaluation.


.

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