Re: How to handle operator of undefined associativity

> [I happen to have C99 here, and they did change it. The grammar
> separates out
> postfix-expression and unary-expression, with postfix-expression
> coming first.
> Offhand, I can't think of any plausible examples where the C99
> grammar would
> parse an expression differently. -John]


John, et. al,


C99 didn't change it, the only difference between the C89 and C99
expression
grammars is addition of compound literals (the "(type-name){...}"
syntax.)
Both C89 and C99 recognise postfix operators as "postfix-expression" and
prefix operators as "unary-expression" as follows:


(6.3.1) primary-expression:
identifier
constant
string-literal
( expression )


(6.3.2) postfix-expression:
primary-expression
postfix-expression [ expression ]
postfix-expression ( argument-expression-list-opt )
postfix-expression . identifier
postfix-expression -> identifier
postfix-expression ++
postfix-expression --


(6.3.3) unary-expression:
postfix-expression
++ unary-expression
-- unary-expression
unary-operator cast-expression
sizeof unary-expression
sizeof ( type-name )


(6.3.3) unary-operator: one of
& * + - ~ !


(6.3.4) cast-expression:
unary-expression
( type-name ) cast-expression


(6.3.5) multiplicative-expresison
cast-expression
multiplicative-expression * cast-expression
... (and so on)


Hope that helps to clarify this thread.


Cheers,


Pat.
[C89 and C99 are the same here, but K&R was, as I recall, a different definition
although the language it accepted seems to be the same. -John]

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