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From: Todd Carnes <toddcarnes@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: confusion about behavior
Date: Mon, 15 Aug 2011 02:04:50 +0000 (UTC)
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On Sun, 14 Aug 2011 15:10:48 -0400, James Kuyper wrote:

> On 08/14/2011 02:56 PM, LJ wrote:
>> int     a = 2;
>> int     b = 3;
>> c = a+++b;
>> What will be the value of c??
>> Shouldn't it be undefined depending upon the interpretation??
> 
> The C standard mandates what's called the "maximal munch" rule; "If the
> input stream has been parsed into preprocessing tokens up to a given
> character, the next preprocessing token is the longest sequence of
> characters that could constitute a preprocessing token." (6.4p4)
> 
> Therefore, there's only one permitted way of parsing the third
> statement:
> 
> 	c = a++ + b;
> 
> That's equivalent to the following statement, where I've inserted some
> unnecessary parenthesis to clarify the order of operations:
> 
> 	c = ((a++) + b);
> 
> Assuming that c has an arithmetic type, the behavior of that statement
> is well-defined: 'a' ends up with a value of 3, and c ends up with a
> value of 5 (converted, if necessary, to whatever the type of c happens
> to be).

So, c would actually be equal to 6. :)

c = ((a++) + b)
c = ((2++) + 3)
c = (3 + 3)
c = 6

I never heard of the "maximal munch" thing. Thanks for the explanation.

Todd