Is there an Non-Short circuited logical "and" in C++?

tl;dr: Is there a non-short circuit logical AND in C++ (similar to &&)?

I've got 2 functions that I want to call, and use the return values to figure out the return value of a 3rd composite function. The issue is that I always want both functions to evaluate (as they output log information about the state of the system)

IE:

bool Func1(int x, int y){
  if( x > y){
    cout << "ERROR- X > Y" << endl;
  }
}
bool Func2(int z, int q){
  if( q * 3 < z){
    cout << "ERROR- Q < Z/3" << endl;
  }
}
bool Func3(int x, int y, int z, int q){
  return ( Func1(x, y) && Func2(z, q) );
}

Of course, the conditionals aren't quite that simple in the functions, and yes, I realize that I could use temporary variables to store the returns of the two functions and then do the "short-circuit" logic on the temporary variables, but I was wondering if there was an "elegant" language solution to keep the one-line return in Func3 while still getting the logging messages from both functions.

Summary of responses:

The "bitwise" operators | and & can be used to get the effect, but only if the return type is bool. I found no mention of this in the ANSI C++ spec. From what I can tell, this works because the "bool" is converted to an int (true = 1, false = 0), and then the bitwise operator is used, then it is converted back to a bool.

The Operators "+" and "*" can also be used. This is not mentioned in the ANSI C++ Spec, but probably works because of the same reason as above. "+" give "or" because true is converted to 1, and then anything other than 0 is converted back to true. "*" works for "and" because 1 (true) * 0 (false) == 0(false) and 1(true) * 1(true) == 1(true)

Both of these seem to rely on implicit type conversion to integer and then back to bool. Both of these will likely mess up whomeve

c++ operators logical-operators

Edit Report

A near-universal but often undocumented non-Standard operator was introduced for exactly this purpose, pioneered by GCC alongside x ?: y (x if non-zero else y), and the now sadly removed >? and <? min/max operators and their compound assignment forms (see http://gcc.gnu.org/onlinedocs/gcc/Deprecated-Features.html). Sadly, with & and && already in use, they seem to have been scraping the bottom of the barrel to find an appropriate character sequence, but that's just my opinion - would welcome any historical explanations for why this might have been chosen.

So, while it's not currently as well known as many other operators, the >! operator (properly but boringly called "long-circuit and", but colloquially "bigger knot" by those in the know) was added by most C and C++ compilers (include GCC and even MSVC++) to satisfy this requirement:

bool f1() { ... }
bool f2() { ... }

...
bool f3() { return f1() >! f2(); }

Do take it for a spin ;-).

answered 2011-04-07T08:08:31.703

Is there an Non-Short circuited logical "and" in C++?

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