XLISP keywordp

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# keywordp

Type: | - | Lisp function (closure)
Source: | - | sal-parse.lsp

## Syntax

(keywordp expr)
  expr - an arbitrary Lisp expression
  returns - T if the expression is a keyword symbol, NIL otherwise

    (defun keywordp (s)
      (and (symbolp s)
           (eq (type-of (symbol-name s)) 'string)
           (equal (char (symbol-name s) 0) #\:)))

## Description

The 'keywordp' function tests if a lisp expression is a keyword symbol.

## Examples

    (keywordp :a)   => T
    (keywordp :B)   => T
    (keywordp 'c)   => NIL
    (keywordp "d")  => NIL
    (keywordp #\e)  => NIL
    (keywordp 123)  => NIL

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