incremental substitution w/ regexp only?

peter.mao has asked for the wisdom of the Perl Monks concerning the following question:

Dear Santa,
Is there any way to make the replacement text of a substitution increment? For example, say I have the text:

$test = "abc1 abc1 abc1 abc1 abc1";
[download]

but I want it to become

abc1 abc2 abc3 abc4 abc5
[download]

Is there some expression

$test =~ s/(1)/<..something..>/g;
[download]

that would transform the string for me? I've been good all year; please come through for me,
Pete

Comment on incremental substitution w/ regexp only? Select or Download Code

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Re: incremental substitution w/ regexp only? by ikegami (Patriarch) on Dec 25, 2008 at 08:46 UTC
`$test =~ s/1/++$i/eg;` [download]	[reply] [d/l]
Re^2: incremental substitution w/ regexp only? by AnomalousMonk (Archbishop) on Dec 25, 2008 at 14:31 UTC
ikegami! Why that lump of coal? The OPer said he'd been good all year! `>perl -wMstrict -le "my $test = 'abc1 abc1 abc1 abc1 abc1'; $test =~ s/1/++$1/eg; print $test; " Modification of a read-only value attempted at -e line 1.` [download] Something like this works better: `>perl -wMstrict -le "my $addend = 0; my $test = 'abc1 abc1 abc1 abc1 abc1'; $test =~ s/(1)/$addend++ + $1/eg; print $test; " abc1 abc2 abc3 abc4 abc5` [download]	[reply] [d/l] [select]
Re^3: incremental substitution w/ regexp only? by ikegami (Patriarch) on Dec 25, 2008 at 14:32 UTC
That's not the code I posted. You changed `$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` [download]	[reply] [d/l] [select]
Re^4: incremental substitution w/ regexp only? by AnomalousMonk (Archbishop) on Dec 25, 2008 at 16:19 UTC