Item 42. Variable Initialization—Or is it?

Difficulty: 3

This first problem highlights the importance of understanding what you write. Here we have four simple lines of code, no two of which mean the same thing, even though the syntax varies only slightly.

What is the difference, if any, between the following? (T stands for any class type.)

T t; 
T t();
T t(u);
T t = u;