On 8/7/2020 9:59 AM, Jairo A. del Rio wrote:
> The original in English, Ozymandias, by Percy Bysshe Shelley, is public
> domain. I extracted the Spanish and French versions from Wikipedia,
> which use a CC BY-SA 3.0 License.
Ok, here is the more robust variant:

\blank
\ifnum\boxlines\EnglishBox=\boxlines\SpanishBox
     \ifnum\boxlines\EnglishBox=\boxlines\FrenchBox
         \ifnum\boxlines\EnglishBox>0
             \dorecurse{\boxlines\SpanishBox}{%
                 \dontleavehmode\llap{\hbox to 1.5em{\txx#1\hss}}%
                                \boxline \EnglishBox#1\par
                 \dontleavehmode\boxline \SpanishBox#1\par
                 \dontleavehmode\boxline \FrenchBox #1\par
                 \blank
             }
         \else
             No content found!\blank
         \fi
     \else
         English and Spanish boxes mismatch!\blank
     \fi
\else
     English and French boxes mismatch!\blank
\fi

Hans

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