$str =~ s/([a-z]),/$repl/eeig;

[download]
seems to do exactly what you require.

Output: 

attempt 1 yields: aAcd

[download]

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In reply to Re: Dynamically generating the replacement part of a substitution by CountZero
in thread Dynamically generating the replacement part of a substitution by chaos_cat

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