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From: jgk@panix.com (Joe keane)
Newsgroups: comp.compilers
Subject: precedence have both ways
Date: Thu, 30 May 2013 23:21:41 -0400 (EDT)
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Anton Ertl <anton@mips.complang.tuwien.ac.at> wrote:
>a<3 AND b<3

This reminds me of a question.

One person designs a language 'C1' with precedence:

    [higher]
    ...
    |
    &
    <, <=, >, <=
    ==, !=
    ...
    [lower]

Some other person designs a language 'C2' with precedence:

    [higher]
    ...
    <, <=, >, <=
    ==, !=
    |
    &
    ...
    [lower]

They're the same besides that.

To compromise, they make a new language 'C3' such that a program is
valid C3 if it is valid C1 and valid C2 -and- both ways mean the same.

Is there some good way to do this -in the grammar-?

[I see gcc has warnings like this.]