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Date: Thu, 09 Dec 2010 05:47:13 +0100
From: Dawid Toton <d0@wp.pl>
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To: caml-list <caml-list@yquem.inria.fr>
Subject: Define parser and printer consistently
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X-Spam: no; 0.00; parser:01 parser:01 ocaml:01 minimized:01 grammar:02 define:02 define:02 construct:02 inconsistent:05 usual:06 function:08 function:08 i'm:09 i'm:09 avoiding:10 

I'm going to define a parser and a printer for a simple grammar.
Is there a way to define both of them in a single construct using some 
existing OCaml tool?

For example, I have a keyword "function". The usual parser would contain 
a mapping like:
"function" -> `Function
and the straightforward printer would do:
`Function -> "function"

What is the best way to combine these definitions, so that duplication 
would be minimized?
To be precise, avoiding duplication is not exactly what I need. I'm 
looking for something that would prevent making inconsistent changes to 
the parser and the printer.

Dawid