$/ variable

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: $/ variable by reyjrar (Hermit) on Aug 21, 2001 at 21:15 UTC
Well, $/ is the input record seperator, its what things like `<>` use to determine when to iterate to the next record. Default is "\n". some examples: `A) echo 'blah;hi;blah;' \|perl -e 'while(<>) { print "$_\n"; }' vs. B) echo 'blah;hi;blah;' \|perl -e '$/=";";while(<>) { print "$_\n"; }'` [download] A outputs: blah;hi;blah; B outputs: blah; hi; blah; If you're interessted in changing this value, you might also look at `split()` which is generally safer to use (especially if you're not using strict and warnings). -brad..	[reply] [d/l] [select]
Re: $/ variable by Hanamaki (Chaplain) on Aug 21, 2001 at 21:34 UTC
A while ago MJD wrote Seven Useful Uses of local for the The Perl Journal. In this article "$/" is covered; and you will get your examples for your better understanding to write good and save Perl code. Hanamaki	[reply]
Re: $/ variable by jryan (Vicar) on Aug 21, 2001 at 21:21 UTC
$/ is the input record seperator (default is "\n"), and if you change it to something else (such as "a" or "\n\n"), perl changes where it seperates "lines" on a file. For instance, here is a script that will read a file on paragraphs (defined as "\n\n") rather than newlines, and print !!!!!PARAGRAPH!!!!! before each one, to let you know that its working: `#!/usr/bin/perl -w use strict; open (FILE, "input.txt"); while (<FILE>) { print "\n!!!!!PARAGRAPH!!!!!\n", $_; }` [download] Here is a sample text file to try it on: (because im nice :)) dstgs dahfgvsd kjghkls djgklsdjgl ksdjglk;j sdkl;ghsd jkljg lkds;j glk +;dsjglk; sdjgkldsjgl ;ksdjgkl;d sjglk;s djgkjdskgjdsjg lkdsjglk;sdjg +l;ksdjglkd sjglkdsjlg sd glsd dstgs dahfgvsd kjghkls djgklsdjgl ksdjglk;j sdkl;ghsd jkljg lkds;j glk +;dsjglk; sdjgkldsjgl ;ksdjgkl;d sjglk;s djgkjdskgjdsjg lkdsjglk;sdjg +l;ksdjglkd sjglkdsjlg sd glsd dstgs dahfgvsd kjghkls djgklsdjgl ksdjglk;j sdkl;ghsd jkljg lkds;j glk +;dsjglk; sdjgkldsjgl ;ksdjgkl;d sjglk;s djgkjdskgjdsjg lkdsjglk;sdjg +l;ksdjglkd sjglkdsjlg sd glsd [download]	[reply] [d/l] [select]
Re: Re: $/ variable by little (Curate) on Aug 21, 2001 at 21:29 UTC
where did you modify $/ in your script? Whether I cant see it or I cant follow your great art of obfuscation. :-) So just for readability I'd suggest to add a line to play with `# (un)comment or modify one of the following #undef $/; #tread all as one line $/ = "d"; # whatever you want it to be` [download] For cool examples on how to use that take a look at Obfuscation. Well sometimes its not only cool but also clever. Have a nice day All decision is left to your taste	[reply] [d/l]
Re: $/ variable by little (Curate) on Aug 21, 2001 at 21:14 UTC
see here:perlman:perlvar Have a nice day All decision is left to your taste	[reply]