Being curious as Perl people will be, i tired an rindex based solution. It unfortunatly would only work with true spaces (" "), and did not fare too well in testing, but, we all learn when things like this happen ... here is my code/output :

Code Addition :
  P_rindex => sub {
    my $x = $X;
    while (1) { my $i = length($x); (rindex($x," ") == $i ? chop : las
+t) };
  },
  F_rindex => sub {
    my $x = $Y;
    while (1) { my $i = length($x); (rindex($x," ") == $i ? chop : las
+t) };
  },

[download]


Output :
Benchmark: running F_plus, F_rindex, F_sexeger, F_while, P_plus, P_rin
+dex,P_sexeger, P_while, each for at least 5 CPU seconds...
    F_plus:  6 wallclock secs ( 5.15 usr +  0.00 sys =  5.15 CPU) @ 37
+600.97/s(n=193645)
  F_rindex:  6 wallclock secs ( 5.45 usr +  0.00 sys =  5.45 CPU) @ 59
+183.30/s(n=322549)
 F_sexeger:  7 wallclock secs ( 5.24 usr +  0.00 sys =  5.24 CPU) @ 59
+187.60/s(n=310143)
   F_while:  7 wallclock secs ( 5.29 usr +  0.00 sys =  5.29 CPU) @ 69
+741.02/s(n=368930)
    P_plus:  5 wallclock secs ( 5.46 usr +  0.00 sys =  5.46 CPU) @ 33
+136.08/s(n=180923)
  P_rindex:  6 wallclock secs ( 5.31 usr +  0.00 sys =  5.31 CPU) @ 60
+743.69/s(n=322549)
 P_sexeger:  5 wallclock secs ( 5.36 usr +  0.00 sys =  5.36 CPU) @ 49
+557.65/s(n=265629)
   P_while:  6 wallclock secs ( 5.09 usr +  0.00 sys =  5.09 CPU) @ 50
+179.17/s(n=255412)
            Rate P_plus F_plus P_sexeger P_while F_rindex F_sexeger P_
+rindex F_while
P_plus    33136/s     --   -12%      -33%    -34%     -44%      -44%  
+   -45%-52%
F_plus    37601/s    13%     --      -24%    -25%     -36%      -36%  
+   -38%-46%
P_sexeger 49558/s    50%    32%        --     -1%     -16%      -16%  
+   -18%-29%
P_while   50179/s    51%    33%        1%      --     -15%      -15%  
+   -17%-28%
F_rindex  59183/s    79%    57%       19%     18%       --       -0%  
+    -3%-15%
F_sexeger 59188/s    79%    57%       19%     18%       0%        --  
+    -3%-15%
P_rindex  60744/s    83%    62%       23%     21%       3%        3%  
+     ---13%
F_while   69741/s   110%    85%       41%     39%      18%       18%  
+    15%--

[download]

As usual, nothing fantastic, but worth the learning experiance.
OH, a sarcasm detector, that’s really useful

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

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