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## Re: Fwd: Junctive puzzles.

From:
Patrick R. Michaud
Date:
February 10, 2005 06:20
Subject:
Re: Fwd: Junctive puzzles.
Message ID:
20050210141944.GC12141@pmichaud.com
```On Thu, Feb 10, 2005 at 10:42:34AM +0000, Thomas Yandell wrote:
> Is the following comment correct?
>
> my \$x = any(2,3,4,5) and any(4,5,6,7); # \$x now contains any(4,5)

Short answer:  I don't think so.

Long answer: I tend to get very lost when dealing with junctions, so
I can be completely wrong.  However, watch the precedence and meanings
of the operators here -- I would think that

my \$x = any(2,3,4,5) and any(4,5,6,7);

results in \$x containing any(2,3,4,5), just as

my \$y = 2 and 3;

results in \$y containing 2 (since C<and> has lower precedence than C<=>).

Even if you fixed the =/and precedence with parens, to read

my \$x = (any(2,3,4,5) and any(4,5,6,7));

then I think the result is still that \$x contains any(4,5,6,7).
It gets interpreted as (from S09):

\$x = any(  2 and 4,       # 4
2 and 5,       # 5
2 and 6,       # 6
2 and 7,       # 7
3 and 4,       # 4
3 and 5,       # 5
# etc...
5 and 6,       # 6
5 and 7,       # 7
);

which ultimately boils down to any(4,5,6,7).

Pm

```