Greetings all,
Update a better way to do it.(than I had previously posted)
Though only tested on a simple case the following should get you your global replace you were looking for. 
$str =~ s/if substr\(([^\)]*)\) in (\([^\)]*\))/my($f,$s)=($1,$2); $f=
+~s!^!\$!; $s=~s!\D!!g; "if substr($f) =~ m#[$s]#"/eg;

[download]
yet another way to do it. 
$str =~ s/in/=~/;
$str =~ s/(?:\s)(\([^\)]*\))/my $s=$1;$s=~s!\D!!g;" m#[$s]#"/e;

[download]

Which outputs 
if substr(acct_trtmt_hsty,1,1) =~ m#[789]#;

[download]
from your original string.


-InjunJoel
"I do not feel obliged to believe that the same God who endowed us with sense, reason and intellect has intended us to forego their use." -Galileo

In reply to Re: Yet another regex question by injunjoel
in thread Yet another regex question by gregor-e

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