That's not the code I posted. You changed $i (9th letter) to $1 (one). My code works fine. 
>perl -le"$_='abc1 abc2 abc3 abc4 abc5'; s/1/++$i/eg; print"
abc1 abc2 abc3 abc4 abc5

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In reply to Re^3: incremental substitution w/ regexp only? by ikegami
in thread incremental substitution w/ regexp only? by peter.mao

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