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

[download]

You need more backslashes :) 

            ( eval "( \$string1 | \$string2 )  =~ tr[$n1][$n1]" ),
            ( eval "( ~\$string1 & \$string2 ) =~ tr[\\$ndiff][\\$ndif
+f]" ),
            ( eval "( \$string1 & ~\$string2 ) =~ tr[\\$ndiff][\\$ndif
+f]" ),
            ( eval "( \$string1 & \$string2 )  =~ tr[$n2][$n2]" ) ),

[download]

In other words, you don't want $string1 and $string2 to be interpolated, but you do want $ndiff interpolated, and prefixed with a backslash, which itself must be escaped.

As you have it, you're eval'ing code like 

    ~0000 & 0101 ) =~ tr[$ndiff][$ndiff]

[download]

but you'd want 

    ~$string1 & $string2 ) =~ tr[\1][\1]

[download]

In case of doubt, when string eval doesn't do what you expect, for debugging purposes always print out the string to be eval'ed...

In reply to Re: Returning transliteration from eval by Anonyrnous Monk
in thread Returning transliteration from eval by albert

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