umhmm you got my typo. i accidentally used $string instead of $str in my post first. that explains the high rates for the regex solution. here is the timing with the typo corrected:

               Rate split_pos grep_split substr_map regexo regex subst
+r_loop unpack
split_pos    5587/s        --       -65%       -69%   -76%  -77%      
+  -79%   -81%
grep_split  15974/s      186%         --       -12%   -32%  -34%      
+  -40%   -45%
substr_map  18051/s      223%        13%         --   -23%  -26%      
+  -32%   -38%
regexo      23474/s      320%        47%        30%     --   -3%      
+  -12%   -20%
regex       24272/s      334%        52%        34%     3%    --      
+   -9%   -17%
substr_loop 26596/s      376%        66%        47%    13%   10%      
+    --    -9%
unpack      29240/s      423%        83%        62%    25%   20%      
+   10%     --
[download]

---

---

• Are you posting in the right place? Check out Where do I post X? to know for sure.
• Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:

  <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>

• Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
• Want more info? How to link or How to display code and escape characters are good places to start.