Can this be done with s/// operator without e modifier in one approach?

Probably, but its a brainfuckadvanced way to go about it :)

1. After success substitution return to the position where substitution started and try to substitute again...

Not sure , but I don't think you can without /e

Here is my non working advanced attempt 

s{
(?<=    \{name_a    )
    (?:
        (?:
            (?<=    \s  )
            |
            (?<=    param_[xy]="    )
            (?:
                (?<=    [^"]   )
            )+
            (?<=    "   )
            
        )
        |
        param_[^xy]\w*="[^"]+"
    )+
(?<=    \}  )
}< eaten >gx;

[download]
I'm probably not understanding (?<=pattern) correctly

The following works 

s/
\{name_a
    (
        (?:
            [^=\s]+ =  "[^"]*"
            |
            \s+
        )+
    )
\}/ FunAt($1) /gex;

sub FunAt {
    join '', '{name_a ', AtAt(@_) ,'}';
}

sub AtAt {
    my %fun = $_[0] =~ m/([^=\s]+) =  ("[^"]*")/gx;
    return join ' ', map { "$_=$fun{$_}" } grep /param_[xy]/, keys %fu
+n;
}

[download]

In reply to Re: RegExp: pos management in global substitution by Anonymous Monk
in thread RegExp: pos management in global substitution by OlegG

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