You mean: (a<b)||(a==b)||(a>b) Double ampersand is logical AND, you want double bars for logical OR. And still, that's equivalent to !(std::is_nan()), un

You mean: (a<b)||(a==b)||(a>b) Double ampersand is logical AND, you want double bars for logical OR. And still, that's equivalent to !(std::is_nan()), unless you're suggesting using the operator on other non-floating-point types which have a similar problem...