For the API function “Particle.connected()”: if you leave off the parens there is NO compile error message! I wasted a day of my life over this. Possibly this applies to other Particle.whatever functions.
Not exactly a compiler but.
It’s just how static class functions are treated.
You can test that with this
class someClass {
public:
static int a;
static int test() { return ++a; }
};
While this can pose a “nasty” trap, there are similar traps that can cause a lot of headache (e.g. if (someVar = 10) instead of if (someVar == 10)) but won’t warrant a compiler error.
While some syntax is perfectly fine it often doesn’t make sense and that’s where compiler warnings would help.
As it happens, your case that’s what the compiler produced
__test.ino:11:19: warning: statement is a reference, not call, to function 'Particle.CloudClass::connect' [-Waddress]
__test.ino:11:19: warning: statement has no effect [-Wunused-value]
However, if you don’t have any real errors in your code you’ll never get to see them - but that is some undesirable behaviour of the Web IDE.
My usual take such things - when I for the life of me can’t find the reason for some strange behaviour - I deliberately add some syntax error (typically a stray } at the end of my code) to provoke an error and then check the warnings.
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that is my worse trap of them all! I hate it when I fall in that one 
@gusgonnet, one way to reduce the risk is to adopt this syntax instead
if (10 == someVar); // that will build fine
if (10 = someVar); // this will throw a compile time error
(it looks 
but prevents some 
)
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oh, I like that option. Thanks!
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