More elementary approaches like demonstrated in Metacpan or perlcommunity.de OTOH are well tested already.

Well the perlcommunity.de solution isn't bulletproof, it won't work well with wrapping or font customizations, the line numbers will get out of sync with the code

the metacpan solution is javascript

In reply to Re^3: Change default style sheet: add line numbers by Anonymous Monk
in thread Change default style sheet: add line numbers by roboticus

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