i must have forgotten how split works...

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Re: i must have forgotten how split works... by kvale (Monsignor) on Mar 09, 2004 at 17:53 UTC
The "." is the problem; this is a regexp in disguise. Try `@DOMAINS = qw( a.com b.com c.com); foreach $DOMAIN (@DOMAINS) { my ($pre, $suf) = split (/\./ , $DOMAIN); print $pre; }` [download] -Mark	[reply] [d/l]
Re: i must have forgotten how split works... by ambrus (Abbot) on Mar 09, 2004 at 17:51 UTC
You have. The first arg of split is a regexp, and dot is a regexp metacharacteer.	[reply]
Re: i must have forgotten how split works... by Juerd (Abbot) on Mar 09, 2004 at 18:36 UTC
my ($pre, $suf) = split ("." , $DOMAIN); The mistake here is that you used `""` for split's first argument. split takes a regex as its first argument. There is one exception: the string `' '` (a single chr(32) character), which is special. Every other string you pass it is interpreted as a regex. If you write it as it is interpreted, the mistake is easier to find: `split /./, $DOMAIN` [download] It is now clear even to human beings that the `.` is a regex. It is a metacharacter, so you need to escape it if you want it to be matched literally: `split /\./, $DOMAIN # or split /[.]/, $DOMAIN` [download] Juerd # { site => 'juerd.nl', plp_site => 'plp.juerd.nl', do_not_use => 'spamtrap' }	[reply] [d/l] [select]
Re: i must have forgotten how split works... by gridlock (Novice) on Mar 09, 2004 at 22:01 UTC
Aaah - - - regexes in Perl can be both a Boon and a Bane! You are splitting on "." - the regex for any character - - so all you are going to get back is what is between each character - - - nothing! So split on "\." You haven't forgotten how Split works - - just overlooked how regexes work! :) /Gridlock a.k.a. Debashis "Codito Ergo Sum"	[reply]
Re: Re: i must have forgotten how split works... by bart (Canon) on Mar 10, 2004 at 09:09 UTC
So a split on "\." No... `"\."` is still `"."`. The constructed string should contain a backslash, so you have to write either `"\\."` or `'\.'` (or `'\\.'`). Constructing a regexp in a string is a bit of a pain. That's one of the reasons why `qr` was invented: `qr/\./` will do the right thing, and still return something that can be treated like a string. Safer still is to stop playing games and just use the regexp, and write `my ($pre, $suf) = split /\./, $DOMAIN;` [download]	[reply] [d/l] [select]