How do I reverse a string or the words in a string?

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

Use reverse in scalar context. It just reverses by bytes or characters. In a list context it will reverse the elements of a list:

$revstr = reverse($str); # reversed by character
$revwords = join(" ", reverse split(/ /, $str));
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Originally posted as a Categorized Question.

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Re: How do I reverse a string or the words in a string? by ariels (Curate) on Dec 03, 2000 at 17:21 UTC
This also works for reversing the order of words, but is trickier. $str = 'hacker. Perl another Just'; ($revwords = $str) =~ s/(\S+)/reverse $1/ge; $revwords = reverse $revwords	[reply]
Re: How do I reverse a string or the words in a string? by pokemonk (Scribe) on Jul 21, 2001 at 04:16 UTC
`#lie about myself $str='i am a sexy bastard'; #split the words @words=split ' ', $str; #revers 'em @words=reverse @words; #join 'em $reversestr=join ' ', @words;` [download] Edit by tye to include wine's suggestion	[reply] [d/l]
Re: Answer: How do I reverse a string or the words in a string? by wine (Scribe) on Jul 21, 2001 at 14:19 UTC
You probably want to joint them with a space: `$reversestr=join ' ', @words;`	[reply] [d/l]
Re: How do I reverse a string or the words in a string? by Anonymous Monk on Apr 16, 2004 at 03:51 UTC
I dont know coding in Perl. I will just tell you an algorithm that strikes me. I expect that Perl has some delimiter for a string like C++ has '\0'. I will refer to the delimiter character to as delimiter The algorithm is simple, Start from the end character and traverse till first. Begin loop if character index= first then print string(current index) else if character = ' ' then /space/ print string(current index) print space set character = delimiter /* Here I am cutting the string. You can cal +l some garbage collecting function to free up the rest of the memory +space/ end if End loop / This algorithm will just print the string in reverse worded way. Bu +t in case you need a reversed string you can go on appending whatever + is printed here to the result string/ [download] Originally posted as a Categorized Answer.*	[reply] [d/l]
Re: How do I reverse a string or the words in a string? by Anonymous Monk on Dec 24, 2002 at 01:24 UTC
what does it say when you reverse fremme neppa venette? Originally posted as a Categorized Answer.	[reply]
Re: How do I reverse a string or the words in a string? by Anonymous Monk on Jan 31, 2003 at 13:51 UTC
fremme neppa venette Originally posted as a Categorized Answer.	[reply]
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