http://www.perlmonks.org?node_id=553895


in reply to Eliminating Left Recursion in Parse::RecDescent

I use the {1} here to emulate the behaviour of an e match. Perhaps theres a better way, if so let me know.

Just use nothing. 

expr      :     term expr_tail
expr_tail : '+' term expr_tail |

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or 

expr      :     term expr_tail
expr_tail : '+' term expr_tail
          |

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or a comment 

expr      :     term expr_tail
expr_tail : '+' term expr_tail
          | # Nothing

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or an empty rule 

expr      :     term expr_tail
expr_tail : '+' term expr_tail
          | Epsilon

Epsilon   :

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In Section Meditations