Xref: utzoo comp.unix.wizards:9428 comp.unix.questions:7630
Path: utzoo!attcan!uunet!yale!husc6!bu-cs!bzs
From: bzs@bu-cs.BU.EDU (Barry Shein)
Newsgroups: comp.unix.wizards,comp.unix.questions
Subject: Re: Tool -flag considered harmful (was: grep replacement)
Message-ID: <23381@bu-cs.BU.EDU>
Date: 16 Jun 88 14:54:53 GMT
References: <7962@alice.UUCP> <4615@vdsvax.steinmetz.ge.com> <10989@cgl.ucsf.EDU> <23325@bu-cs.BU.EDU> <7985@alice.UUCP>
Organization: Boston U. Comp. Sci.
Lines: 23
In-reply-to: andrew@alice.UUCP's message of 15 Jun 88 17:35:37 GMT


From andrew@alice
>there are some technical problems with printing context, particluarly
>if you want regular expreesion-defind contexts. it means you have to be
>able to run the sodding regexp stuff backwards thru the text. it also
>means keeping a lot of buffer which is more than a little repugnant.

Why not look for "starts" as you search forward and (re)start
buffering from there? No need to search backwards after the match, in
fact it would be counter-productive (either you need to seek a pipe or
save everything, of course saving a seek pointer to last start on
streams that support it might be a rational optimization, but it's not
necessary if you save starts as you go.)

I don't know what "repugnant" means in any context that can be answered.

>despite all this, it is feasible but not trivial to add context stuff.
>i won't do it though.

Of course, that is your decision, I was just trying to provide helpful
comments as was requested.

	-Barry Shein, Boston University