Why Why

int i=5;
i = ++i;
print(i);//prints 6

int i=5;
i = i++;
print(i);//prints 6

int i = 5;
i = i++ + ++i;
print(i);//prints 11?...........NO ITS 12. WHY

You're an idiot. Read all of the following:
* Structure and interpretation of Code Tags
* http://www.wikihow.com/Use-English-Punctuation-Correctly
* K&R

because it's undefined behaviour.
(here prints 13)

I'll give you two out of ten for being so obvious it's almost insulting in itself.

What the hell language even is that? IHBT

The behaviour of i = i++ + ++i; is undefined? Really? Wow, what a huge piece of shit of a language they have there. This expression should expand to:


(+ (let ((k i))
        (set! i (+ i 1)) k)
   (begin (set! i (+ i 1))
          i))

which will return 12. With Racket it's easy to understand why: you evaluate subexpressions from left to right. The first argument to + does return the original i (5), but it modifies i before the second argument is evaluated, which ends up returning the original i incremented twice.

So, what can we learn from this? Side effects are evil. Use functional programming.

>>6
Or just don't modify an object twice between sequence points.

I can't wait fot lambdas to be standard Sepples.

I can't wait fot Sepples to be standard lambdas.

I can't wait fot standard lambdas to be Sepples.

>>6
Nowhere in the C standard does it say that the order of evaluation should be left-to-right. Rightly so: it allows programmers to follow the mathematical conventions for operator precedence in infix notation without having to use fucktons of parentheses.

>>6
Scheme doesn't specify the order of evaluation of sub expressions either. This gives freedom to the implementor of where to put intermediate values.

What a stupid thing to bash a language for. When would you ever do i = i++ + ++i; anyway?

>>6
Your reasoning only shows that you know nothing of what that sequence of machine instructions is produced for that expression.

>>13
Not necessarily. For instance, >>6 is also showing me that Lisp programmers are nitwits.

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