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# and

Type: |
- |
special form (fsubr) |

Source: |
- |
xlcont.c |

## Syntax

- (and [
*expr1* ... ])
*exprN* - an expression

returns - NIL if any expression evaluates
to NIL , otherwise the value
of the last expression

**Note:** evaluation of expressions stops after the first
expression that evaluates to NIL

## Description

The 'and' special form evaluates a sequence of expressions and returns
the effect of a logical AND on the expressions. If, at any point, an
expression is NIL,
NIL is returned as the result of the 'and'
function. If all of the expressions have a
non-NIL value, the value of the last
expression is returned as the result. Evaluation of the expressions will
stop when an expression evaluates to NIL,
none of the subsequent expressions will be evaluated. If there are no
expressions, 'and' returns T
as its result.

## Examples

(and T "boo" "hiss" T "rah") ; returns "rah"
(and T T T T) ; returns T
(and) ; returns T
(and (princ "hi") NIL (princ "ho")) ; prints hi and returns NIL
(and (princ "hi") (princ " de ") ; prints hi de ho
(princ "ho")) ; returns "ho"
(setq a 5) (setq b 6) ; set up A and B
(if (and (numberp a) ; if A is a number
(numberp b) ; and B is a number
(< a b) ) ; and A<B
(print "A is less than B") ; THEN do this
(print "something else happened")) ; ELSE do this
; prints "A is less than B"

See the
and
special form in the XLISP 2.0 manual.

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