[Haskell-cafe] Re: [Parsec] Backtracking with try does not work for me?

Stephane Bortzmeyer bortzmeyer at nic.fr
Mon Jul 31 08:56:06 EDT 2006

On Mon, Jul 31, 2006 at 12:57:04PM +0200,
 Udo Stenzel <u.stenzel at web.de> wrote 
 a message of 59 lines which said:

> Now 'optional x' always succeeds, so the 'try' is useless where you
> placed it.  You need to 'try' the argument to 'optional':

It works, too. Many thanks for the code and the explanation.
> You could also factor your grammar 

It is a language I do not control, so I prefer to keep the grammar as
close as possible from the official specification.

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