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BNFC / bnfc

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BNFC does not allow empty declarations in .cf files #215

Closed andreasabel closed 6 years ago

andreasabel commented 7 years ago

BNFC (haskell) accepts totally empty input files, but not

;

It should also allow empty declarations consisting just of a ;. This would allow a style like

-- comment
; Rule. S ::= P
-- comment
; Rule2. S ::= Q

where semicolons are aligned at the first column.

andreasabel commented 6 years ago

This can be fixed by defining custom Def lists with the extra rule:

_. [Def] ::= ";" [Def] ;