use the modifier 'e' on your regex .... 

   s/a/substr($b,0,1)/e ;
   s/b/substr($b,1,1)/e ;

[download]

(definition:) it evaluates the right hand side of s/// as an expression .

Enjoy,
Mickey

In reply to Re: regexp and a perl function by mickeyn
in thread regexp and a perl function by Anonymous Monk

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