Oh, I was hoping someone would bite. ;)

That regex is worse. You'd think by breaking \s+ down into \s*\s, you'd get the best of both worlds -- the "1 or more" meaning, and the "trailing character" optimization. No such luck. In fact, the regex does MORE work, because of backtracking. :(

You see, Perl doesn't even see if the string has ANY trailing whitespace if you do /\s+$/. Meaning it takes a while to fail for a string like "a b c d e f g h i j k l m n o p q r s t u v w x y z". How sad. 

# try this, and be sad :(

use re 'debug';

"abc  def  ghi" =~ /\s+$/;
"abc  def  ghi" =~ /\s*\s$/;

[download]
The output (if you understand it) will upset you. Well, it upset me.

_____________________________________________________
Jeff japhy Pinyan: Perl, regex, and perl hacker.
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to Re: Re: japhy blabs about regexes (again) by japhy
in thread japhy blabs about regexes (again) by japhy

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