Re: 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]
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;` [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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