Are people actually boggled by the "++" operator? If they can barely wrap their minds around that, why are they even in programming? Seriously!
Firstly there is simply the `i++`, which is redundant with `i+=1`, but it's also very easy to understand syntactic sugar. Keep it or leave it, no big deal.
Then there is the more advanced and very subtle use of the return value:
int i = 3;
while (i--) {
printf("%d, ", i); // What does this print?
}
EDIT: Fixed code formatting
I agree that you can write confusing code with ++, but that doesn't mean it should be banned! (Like they did with Swift). The ++ operators still are very useful. Also there are arguments that they're more correct than +=1 operations. I see ++ as meaning, "go to the next thing."
For example, the following operation sort of doesn't make sense:
char c = f();
c += 1;
c += '\001';
Same goes with pointers. They're memory addresses... but what happens of you add 1 to a memory address? Should you get the address plus one, or should you step over to the next object?
int i = 3;
while (i--) {
printf("%d, ", i); // What does this print?
}
printf("%d, ", i); 2, 1, 0
2, 1, 0, %
If you're using zsh:
> When a partial line is preserved, by default you will see an inverse+bold character at the end of the partial line: a ‘%’ for a normal user or a ‘#’ for root. If set, the shell parameter PROMPT_EOL_MARK can be used to customize how the end of partial lines are shown.
See http://zsh.sourceforge.net/Doc/Release/Options.html#Promptin...
I read the instruction as: "Set i to 3. Subtract 1 then print until false."
i = 3
3 - 1 = 2, print
2 - 1 = 1, print
1 - 1 = 0, print
0 = false, stop
It doesn't compile in C++. Conditions have to be booleans. i-- is an integer :D
In C, 'true' is defined as anything else than '0', there is no proper boolean types, i-- is an integer which is perfectly okay for conditions, the condition is equivalent "while (i != 0)".
There might be some variations, errors and warnings depending on the compilers, the strictness level and the revision of the language chosen.
I am definitely talking about C++
int x = 1;
bool y = x;
# cl.exe /W3 main.c
http://stackoverflow.com/a/31552168/5994461
This stackoverflow message talks about the specs for C11, and the first comment adds information on the C++03 spec. It seems that implicit cast from integer to boolean is allowed... under all circumstances... depending on what specification the compiler is following :D
For future references, I'll just summarize this as "C and C++ are minefields". We'll just add that to the list of WTF behaviors.
By the way, if you think that "C has had bool for 19 years" [the C99 spec specifically]. You clearly didn't work in C for long enough with a large variety of tools. The world is bigger than just GCC.
I believe that the justification for that is that you'll often want to do e.g.
while (node) {
node.val += 3;
node = node->next;
}
while (std::cin >> x >> y) { ... }To make an analogy, I can perfectly understand null and what it does. My objection to null as a language feature is not based on not understanding it and what it does.