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

First, \1, etc are regex patterns. You want $1, etc.

Secondly, you have some serious misconception about the replacement expression.
Without /e, it's a double-quoted string literal that evaluates to the replacement.
With /e, it's a Perl expression which evaluates to the replacement. 

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

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Re^2: How to eval an array element in regex's substitution
by pysome (Scribe) on Oct 27, 2010 at 04:48 UTC
    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 ?

    [download]
    How to eval the $s's value？
[reply]
[d/l]
      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;

      [download]

      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;

      [download]
[reply]
[d/l]
[select]

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