XLISP nil

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# nil

Type: | - | system constant
Source: | - | xlsym.c

## Syntax

nil

## Description

The 'nil' constant represents the empty list or the false value, as oppossed to the true value [the symbol T ]. 'nil' can be written as the three character symbol 'nil' or as the empty list ().

## Examples

    (setq myvar nil)                     ; set MYVAR to False
    (setq myvar 'nil)                    ; NIL and 'NIL evaluate to NIL
    (setq myvar ())                      ; () is the empty list = NIL
    (setq myvar '())                     ; () and '() evaluate to NIL
    (if nil (print "this won't print")   ; if/then/else
            (print "this will print"))

Note: You can not change the value of NIL.

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Nyquist / XLISP 2.0 - Contents | Tutorials | Examples | Reference