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in reply to Re: How to eval an array element in regex's substitution
in thread How to eval an array element in regex's substitution

Thank your very much.
Another question, maybe i refer to capture the square brackets ,
and then "eval" the array element. Such as: 
$s =~ s/(\[\d{1,2}\])/$a$1/g; #output Hello $a[2]$a[1]

# eval '$s="$s";'; ## Here ?

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How to eval the $s's value？

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Re^3: How to eval an array element in regex's substitution
by ikegami (Patriarch) on Oct 27, 2010 at 06:48 UTC 
    my $s = 'Hello [2][1]';
my @a = ('x','y','z');
my $array_name = 'a';
{
   no strict 'refs';
   $s =~ s/\[(\d{1,2})\]/$array_name->[$1]/g;
}
print $s;

    [download]

    Better: 

    my $s = 'Hello [2][1]';
my @a = ('x','y','z');
my $array_name = 'a';
my $array_ref = do { no strict 'refs'; \@$array_name };
$s =~ s/\[(\d{1,2})\]/$array_ref->[$1]/g;
print $s;

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    But why do you want to use variable variable names?

    Good: 

    my $s = 'Hello [2][1]';
my @a = ('x','y','z');
my $array_ref = \@a;
$s =~ s/\[(\d{1,2})\]/$array_ref->[$1]/g;
print $s;

    [download]

    Simplified: 

    my $s = 'Hello [2][1]';
my @a = ('x','y','z');
$s =~ s/\[(\d{1,2})\]/$a[$1]/g;
print $s;

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