*unbound*

Type:	-	system constant
Source:	-	xlinit.c, xlsym.c

Syntax

 *unbound*

Description

The *unbound* system constant is used to indicate when a symbol has no value. *unbound* is set to the value *unbound*. This means that the system thinks the symbol *unbound* has no value.

Examples

*unbound*            ; error: unbound variable
(setq a 5)           ; returns 5
a                    ; returns 5
(setq a '*unbound*)  ; returns *UNBOUND*
a                    ; error: unbound variable

See the *unbound* system constant in the XLISP 2.0 manual.

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