NAME
    isdefined - whether a string names a defined function

SYNOPSIS
    isdefined(str)

TYPES
    str		string

    return	0, 1, or 2

DESCRIPTION
    isdefined(str) returns 1 if str is the name of a builtin function,
    2 if str is the name of a user-defined function, 0 otherwise.

EXAMPLE
    > isdefined("abs")
	1

    > isdefined("fun")
	0

    > define fun() { }
    fun() defined

    > isdefined("fun")
	2

    > undefine fun
    > isdefined("fun")
	0

LIMITS
    none

LIBRARY
    none - XXX ?

SEE ALSO
    define, undefine,
    isassoc, isatty, isblk, isconfig, iserror, iseven, isfile,
    ishash, isident, isint, islist, ismat, ismult, isnull, isnum, isobj,
    isobjtype, isodd, isprime, isrand, israndom, isreal, isrel,
    issimple, issq, isstr, istype