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From: emv@math.lsa.umich.edu (Edward Vielmetti)
Newsgroups: comp.lang.perl
Subject: Re: Deleting (Only) First Blank Line in File
Message-ID: <EMV.90Jul1175629@urania.math.lsa.umich.edu>
Date: 1 Jul 90 21:56:29 GMT
References: <1651@fallst.UUCP> <1990Jun30.214249.15211@iwarp.intel.com>
Sender: usenet@math.lsa.umich.edu
Distribution: comp
Organization: University of Michigan Math Dept., Ann Arbor MI.
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In-Reply-To: merlyn@iwarp.intel.com's message of 30 Jun 90 21:42:49 GMT

In article <1990Jun30.214249.15211@iwarp.intel.com> merlyn@iwarp.intel.com (Randal Schwartz) writes:

   | Solutions other than those using 'perl' are preferred.

   But, since you didn't say *necessary*, how about:

   perl -ne 'print unless /^$/ && $once++;'

hm, nice.  how about this problem: printing the first 10 lines after
a signal line?  I would think it could be done with the .. operator, namely

	perl -ne 'if (/===/) {$l = $. + 10 ;} ; if (/===/ .. $l) {print;} '

but this prints only the === line and the one following.  a test with digits
shows that it works as expected for this:

	perl -ne 'if (/===/) {$l = $. + 10 ;} ; if (/===/ .. 50) {print;} '

which lead me to experiment with the following which worked

	perl -ne 'if (/===/) {$l = $. + 10 ;} ; eval "if (/===/ .. $l) {print;}"; '

the eval appears to be neccesary in order to force the .. to be
interpreted in a scalar context, but I guess I don't really understand
the man page, & in retrospect a simple loop would have done the trick
OK.

--Ed

Edward Vielmetti, U of Michigan math dept <emv@math.lsa.umich.edu>