What's a fast way to test if 2 rectangles are intersecting?

A search on the internet came up with this one-liner (WOOT!), but I don't understand how to write it in Javascript, it seems to be written in an ancient form of C++.

struct
{
    LONG    left;
    LONG    top;
    LONG    right;
    LONG    bottom;
} RECT; 

bool IntersectRect(const RECT * r1, const RECT * r2)
{
    return ! ( r2->left > r1->right
        || r2->right left
        || r2->top > r1->bottom
        || r2->bottom top
        );
}