Trailing spaces

TeKk9 has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Trailing spaces by thraxil (Prior) on Jun 22, 2001 at 01:03 UTC
`$string =~ s/\s+$//;` anders pearson // digital samurai personal // http://www.columbia.edu/~anders/ weblog // http://thraxil.dhs.org/	[reply] [d/l]
Re: Trailing spaces by VSarkiss (Monsignor) on Jun 22, 2001 at 01:04 UTC
You're very close: `$string =~ s/\s$//;` As far as I know, `tr` can't tell position. One space is the same as any other. Hence the `s///`. HTH Update: Oops. Forgot the quantifier. YA Update*: Abigail is correct, `+` is better. That's what happens when you rush to fix an "oops"....	[reply] [d/l] [select]
Re: Trailing spaces by Abigail (Deacon) on Jun 22, 2001 at 02:29 UTC
Using `s/\s$//` is not to be recommended, as that will always match (and hence do a substitution). Use of `` means zero or more times. Use `+` instead. -- Abigail	[reply] [d/l] [select]
Re: Trailing spaces by Beatnik (Parson) on Jun 22, 2001 at 13:36 UTC
Also check pretty similar How can I strip an arbitary number of leading spaces from a string?. Greetz Beatnik ... Quidquid perl dictum sit, altum viditur.	[reply]
Re: Trailing spaces by IcyHot (Novice) on Jun 23, 2001 at 01:08 UTC
It's best to use the end-of-string or end-of-line metacharacters which solves the problem of not getting rid of the spaces between "Last" and "Known". The dollar-sign $ character means end of line or end of string if the string has only one line. The \s means a space so you don't need a physical space " " It's also probably better to use s/// (substitution) rather than tr/// (tranliteration) although either should work. `s/\s$//; # means substitute zero or more spaces # before end-of-line with NOTHING (get rid of them)` [download] Here's some basic sample code: `$jo = "Mary had a little lamb "; print $jo . "blah\n"; $jo =~ s/\s$//; # get rid of the spaces print $jo . "blah\n";` [download] Here's the output: `Mary had a little lamb blah # spaces at end of $jo Mary had a little lambblah # spaces be gone!` [download] --------------------------------------------------------- There's also the \z character which means end of string, no matter what (ragardless of any newlines). \Z matches anything right before a newline at the end of a string or the end of a string if there is no newline. The $ character is pretty much the same as \Z unless the string has several newlines (string is a paragraph) and then the $ would match before a newline character, not necessarily the end of the string. Therefore, if you have a paragraph and want to get rid of spaces at the end of EVERY line, you could do something like: `s/\s*$//gm;` [download] The /g applies the substitution to multiple matches, while /m tells Perl that there are Multiple lines (as opposed to /s Single line) \A and ^ are the same as \Z and $ but in the begging of a line or a string - hey, A is the first and Z is the last letter of the alphabet :) If you're not too familiar with regular expressions, you should read up on the different metacharacters you can you (don't lose your marbles, though - it can get hectic)	[reply] [d/l] [select]
Re: Trailing spaces by Anonymous Monk on Jun 22, 2001 at 13:12 UTC
$string =~ s/ +$//; Allen	[reply]
Re: Trailing spaces by princepawn (Parson) on Jun 22, 2001 at 01:07 UTC
I recommend String::Strip instead of all that comic-book profanity above {grin}. `@foreign = qw(HTTP HTML CGI SQL fixed-length-data xSV-data); @chromatic = @tilly = map { "$_ is plain text, easily manipulated in Perl" } @foreign; @princepawn = map { "find something on CPAN to manipulate $_" } @forei +gn;` [download]	[reply] [d/l]
Re: Trailing spaces by prarie dawn (Sexton) on Jun 22, 2001 at 06:33 UTC
What if there are two non-trailing spaces together that need preserving?	[reply]
Re: Re: Trailing spaces by dirthurts (Hermit) on Jun 22, 2001 at 08:50 UTC
`$string =~ s/\s+$//;` will work fine for that, the $ anchors the pattern to the end of the string. Any other spaces that aren't at the end of the string are left as is.	[reply] [d/l]