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From:	"Hamish (H.I.) Macdonald" <hamish@bnr.ca>
Message-ID: <"18857 Fri Jan 15 12:19:31 1993"@bnr.ca>
To:	rc@hawkwind.utcs.toronto.edu
Subject: what does ~! mean? 

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.