DB<57> say "a\\b" =~ tr/a\b/xyz/r # expected 'xyz'
x\b

  DB<58>

##</code><code>##

C:\tmp\t_wperl>perl -E"say 'a\\b' =~ tr/a\b/xyz/r # expected 'xyz'"
x\b

C:\tmp\t_wperl>