why not just eval?
Because with eval, you must worry about delimiters. For example, if either string had contained "/", the eval example given elsewhere in this thread would fail. Also, eval invites disaster in a proxy-privilege environment (like CGI or other daemons).

The lookup table isn't hard to create: 

## initialization
my $old = 'abc';
my $new = 'xyz';
my %table; @table{split //, $old} = split //, $new;
my $table_re = join '|', map quotemeta reverse sort keys %table;

## the deed
my $string = 'abracadabra';
$string =~ s/($table_re)/$table{$1}/g;

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-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to Re^3: How to use a variable in tr/// by merlyn
in thread How to use a variable in tr/// by perl-novice

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