The results of this formulation are: 
                 Rate substr_lval       subst     reverse substr_mod s
+ubstr_copy
substr_lval  489949/s          --         -9%        -37%       -67%  
+      -69%
subst        539218/s         10%          --        -31%       -63%  
+      -66%
reverse      776376/s         58%         44%          --       -47%  
+      -52%
substr_mod  1473954/s        201%        173%         90%         --  
+       -8%
substr_copy 1606272/s        228%        198%        107%         9%  
+        --

[download]
Not hard to see the problem with $_. That said I'm not sure that what you say about how things shouldn't be in a sub is correct. Shouldn't it factor out since it would be true for all cases?

--hsm

"Never try to teach a pig to sing...it wastes your time and it annoys the pig."

In reply to Re^2: Ways to delete start of string by hsmyers
in thread Ways to delete start of string by hsmyers

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