AND/OR chains in C

Question

I'm pretty much positive about this, but just to be on the safe side:

Does the C standard guarantee that AND chains (A && B && ...) will be evaluated left to right, and that evaluation will stop as soon as there's a 0?

Same question for OR. (As soon as there's a 1)

Can I count on this for other C-style languages?

Is this code safe:

if (somePtr!=NULL && somePtr->someMember==123)
{
     ...
}

Answer 1

Yes, it is guaranteed for C, C++ and C#. The same goes for Delphi with "short curcuit evaluation" enabled.

This is behaviour numerous lines of code rely on to this moment.

Answer 2

Yes, it is standardised by both C and C++.

Answer 3

Yes, your assumptions about the order of operations in C are correct and the code snippet will work as intended. I would take other "C-style" languages on a case-by-case basis.

Answer 4

Yes it does.

I have seen people who thought that was unclear, and replaced &&'s with this form:

if (a)
if (b)
if (c)
if (d) {
}

Personally I think that's kinda ugly.