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Re: keyword_set bug or feature [message #4212 is a reply to message #4205]

Sat, 13 May 1995 00:00

rivers
Messages: 228
Registered: March 1991

Senior Member

In article <PHIL.95May12090139@peace.med.ohio-state.edu>, phil@peace.med.ohio-state.edu (Phil) writes:
> Thanks to those who responded to my ? concerning common blocks.
>
> I just can across another 'feature' and was wondering if others felt
> that it is really a 'bug' or if there is some way to over come it. It
> has to do with keywords in functions or procedures. I use several and
> check to see if the are set using
>
> IF NOT(keyowrd_set(key)) THEN BEGIN
> ;set a default value here
> ENDIF
>
> The problem comes in if the user wants to set key = 0. If so then it
> appears to the above test that the keyword is not set even though in
> the function call the user typed
>

keyword_set is intended for use with switches, i.e. parameters which can either
be 0 or 1. 0 or not present means switch not set, 1 means switch set.

If you want to detect that the keyword is present, even if the value is zero,
then you should use n_elements().

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Mark Rivers (312) 702-2279 (office)
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[Message index]

		Re: keyword_set bug or feature By: chase on Mon, 15 May 1995 00:00
		Re: keyword_set bug or feature By: rivers on Sat, 13 May 1995 00:00
		Re: keyword_set bug or feature By: peter on Fri, 12 May 1995 00:00

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