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Re: i = i++

On Wed, Jan 10, 2001, the greycells of P k j ~ c K expressed:

> read some C faqs . they say  changing a variable in a statement which refers it twice isn't valid . so

The question of valid or invalid does not figure out here. The fact is that, the ANSI standard says
nothing about such statements, these are called "statements with side-effects".
The outcome is not predictable, as EVERY compiler is free to implement it as it wishes.

Essentially, K&R advises to avoid such statements with side effects. It is _NOT_ a good programming
practice at all.

People administering C language tests should avoid asking such questions, as they make no sense. ;-)
(We have a tendency to make the C test as arcane as possible) ;-) 

> anything like 
> ++i = i;  or 
> ++i = i++;  or 
> printf("%d %d",++i,i++);     are not valid & thus may differ from compiler to compiler

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