How to escape dollar sign ($) in a string using perl regex

Question

I\'m trying to escape several special characters in a given string using perl regex. It works fine for all characters except for the dollar sign. I tried the following:

Answer 1

You don't need a hash if you're replacing each character with itself preceded by a backslash. Just match what you need and put a backslash in front of it:

s/($re)/"\\$1"/eg;

To build up the regular expression for all of the characters, Regexp::Assemble is really nice.

use v5.10.1;
use Regexp::Assemble;

my $ra = Regexp::Assemble->new;

my @specials = qw(_ $ { } # % & );

foreach my $char ( @specials ) {
    $ra->add( "\\Q$char\\E" );
    }

my $re = $ra->re;
say "Regex is $re"; 

while(  ) {
    s/($re)/"\\$1"/eg;
    print;
    }

__DATA__
There are $100 dollars
Part #1234
Outside { inside } Outside

Notice how, in the first line of input, Regexp::Assemble has re-arranged my pattern. It's not just the glued together bits of the parts I added:

Regex is (?^:(?:[#$%&_]|\{|\}))
There are \$100 dollars
Part \#1234
Outside \{ inside \} Outside

If you want to add more characters, you just put the character in @specials. Everything else happens for you.