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[REBOL] howto non_existance- check?

From: riachtchenko::docutec::de at: 14-Dec-2000 18:30

Hi all, sorry, i certainly could 've seen the solution - but coud't find it now ;-)
>> f: func [w ] [either [ value? 'w ] [ do 'w][print "no way..."]] >> value? 'm
== false
>> x
== 10
>> f x
== 10
>> f m
** Script Error: m has no value. ** Where: f m
>> f 'm
== m
>>
thank you Sascha