Habitual backslasher ikegami might have something to say about it but single (non-interpolating/literal) quotes can be a bit easier to read. 

            ( eval '( $string1 | $string2 )  =~ tr[$n1][$n1]' ),
            ( eval '( ~$string1 & $string2 ) =~ tr[$ndiff][$ndiff]' ),
            ( eval '( $string1 & ~$string2 ) =~ tr[$ndiff][$ndiff]' ),
            ( eval '( $string1 & $string2 )  =~ tr[$n2][$n2]' ) ),

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Update: my eyes are getting old. I missed the interpolation in the trs.

In reply to Re^3: Returning transliteration from eval by Your Mother
in thread Returning transliteration from eval by albert

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