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Re: _extra keyword [message #43362 is a reply to message #43326]

Thu, 07 April 2005 12:52

Michael Wallace
Messages: 409
Registered: December 2003

Senior Member

> The problem (and beauty) of _EXTRA is that unknown
> keywords are silently ignored by the procedures that
> use this mechanism. In practice, this means that if you
> misspell a keyword, no one ever complains, but the keyword
> has no effect, either. I strongly suspect that is your
> problem.
>
> One way to handle this problem is to use the _STRICT_EXTRA
> keyword (in place of _EXTRA) on the last procedure or function
> in the keyword inheritance chain. The _STRICT_EXTRA *will*
> complain if it gets a keyword it doesn't understand, so you
> can use this to trap for misspelled keywords.

Just as a programming style note, when I'm in a routine which only
passes extra keywords to one other routine, I always use _STRICT_EXTRA.
That guarantees me that if I mistype something or get a wrong
keyword, the error will be caught.

The only time I don't use _STRICT_EXTRA is if I'm going to pass the
extra arguments to at least two other routines. In this case you'd want
the first routine to ignore the keywords associated with the second and
vice versa. However, I only recommend doing this when it's really
necessary. I've found that extra keywords are much easier to debug and
maintain when you're able to use _STRICT_EXTRA.

-Mike

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[Message index]

		_extra keyword By: antonioolita on Fri, 01 April 2005 02:12
		Re: _extra keyword By: David Fanning on Thu, 07 April 2005 12:58
		Re: _extra keyword By: Michael Wallace on Thu, 07 April 2005 12:52
		Re: _extra keyword By: David Fanning on Thu, 07 April 2005 05:33
		Re: _EXTRA KEYWORD By: dandan on Wed, 04 November 2009 23:37
		Re: _EXTRA KEYWORD By: David Fanning on Wed, 04 November 2009 15:22
		Re: _EXTRA KEYWORD By: David Fanning on Wed, 11 November 2009 19:01
		Re: _EXTRA KEYWORD By: Michael Galloy on Wed, 11 November 2009 18:54
		Re: _EXTRA KEYWORD By: David Fanning on Wed, 11 November 2009 17:36
		Re: _EXTRA KEYWORD By: ben.bighair on Wed, 11 November 2009 16:23
		Re: _EXTRA KEYWORD By: mankoff on Wed, 11 November 2009 14:47

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