How do you map-replace characters in Javascript similar to the 'tr' function in Perl?

Question

I\'ve been trying to figure out how to map a set of characters in a string to another set similar to the tr function in Perl.

I found this site that sh

Answer 1

In Perl, one can also write

tr{-_}{+/}

as

my %trans = (
   '-' => '+',
   '_' => '/',
);

my $class = join '', map quotemeta, keys(%trans);
my $re = qr/[$class]/;

s/($re)/$trans{$1}/g;

This latter version can surely be implemented in JS without much trouble.

(My version lacks the duplication of Jonathan Lonowski's solution.)