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From: "Hamish (H.I.) Macdonald" <hamish@bnr.ca>
To: rc@hawkwind.utcs.toronto.edu
Subject: what does ~! mean?
Date: Fri, 15 Jan 1993 07:20:00 -0500	[thread overview]
Message-ID: <"18857 Fri Jan 15 12:19:31 1993"@bnr.ca> (raw)

I've noticed the use of ~! in trip.rc in a few places:

    if (~! `` '' {echo --} $nl)
            fail echo --

I don't understand what this is supposed to do.

According to the grammar, TWIDDLE should be followed by an optional
caret and words.  I don't see anything in the grammer allowing ~ to be
followed by a BANG (unless the ! is a word, in which case there should
be white space after the TWIDDLE, no?).

Is the sense of this backwards?  Should it be '! ~' (or !~) ?

Thanks,
 Hamish.


             reply	other threads:[~1993-01-15 17:21 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1993-01-15 12:20 Hamish (H.I.) Macdonald [this message]
1993-01-15 21:26 Byron Rakitzis

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