enum type in C++

Question

This works:

enum TPriority 
{
    EPriorityIdle = -100,
    EPriorityLow = -20,
    EPriorityStandard = 0,
    EPriorityUserInput = 10,
    EPriorityHigh = 20
};

TPriority priority = EPriorityIdle; 

But this doesn't work:

TPriority priority = -100;

Any reason?

Answer 1

It works too, but you need explicit type

TPriority priority = (TPriority)-100;

Answer 2

shortly put: it defeats the purpose of having an enum