XLISP characterp

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# characterp

Type: | - | predicate function (subr)
Source: | - | xlbfun.c

## Syntax

(characterp expr)
  expr - the expression to check
  returns - T if the value is a character, NIL otherwise

## Description

The 'characterp' predicate function tests if 'expr' evaluates to a character. T is returned if 'expr' evaluates to a character, NIL is returned otherwise.

## Examples

    (characterp #\a)       => T    ; character
    (setq a #\b)           => #\b
    (characterp a)         => T    ; evaluates to a character
    (characterp "a")       => NIL  ; string
    (characterp '(a b c))  => NIL  ; list
    (characterp 1)         => NIL  ; integer
    (characterp 1.2)       => NIL  ; float
    (characterp 'a)        => NIL  ; symbol
    (characterp #(0 1 2))  => NIL  ; array
    (characterp nil)       => NIL  ; NIL

See also:

- Contents → Predicate Functions
- Contents → Character Functions

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