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JkWhoSaysNi
01-23-2007, 12:15 AM
Why doesn't this work:

variable ? function() : function2();

yet this does:

x = variable ? function() : function2();

The first example never gets processed. It's easier and neater than using

if (var) {
function();
}
else {
function2();
}

Tolnaftate2004
01-23-2007, 01:09 AM
variable ? function() : function2();

You've written it as if it were some sort of function. This is like doing
1+1;
It's just an operator.

Falcor
01-23-2007, 01:21 AM
Why doesn't this work:

variable ? function() : function2();

yet this does:

x = variable ? function() : function2();

The first example never gets processed. It's easier and neater than using

if (var) {
function();
}
else {
function2();
}

I recommend you don't use the ternary operator for anything aside from simple substitutions. eg... (x>1? 0 : 1)
Its a very bad programming practice to use it as flow-control. It's not intended for that.

JkWhoSaysNi
01-23-2007, 01:33 AM
Why? It's only like a 2 line case statement.

It's much neater than either a case statement or if / else and has the same result.

Falcor
01-23-2007, 01:52 AM
Why? It's only like a 2 line case statement.

It's much neater than either a case statement or if / else and has the same result.

You sacrifice code clarity for a few less characters. if(condition) this; else that; makes more sense than (condition? this : that) when you glance at your code. You shouldn't have to comment code that documents itself either.

There is a reason why ?: is considered an operator and not flow control. Because it isn't.

In reference to your original question, the compiler probably skips over statements that don't make sense like 1+1; Why waste CPU resources on some stand alone expression whose computed value is never used? The assumption the compiler makes is that (?:) is used for expressions, not for program flow. To act otherwise is dangerous, especially if the nature of the compiler changes, it may break your code.