One of the most interesting grammars of any programming languages. Three of these things belong together, and one is something altogether different...

SomeType t = u; SomeType t(u); SomeType t(); SomeType t; 

All but the third one define a SomeType on the stack and initialize it (with u in the first two case, and the default constructor in the fourth. The third one is actually declaring a function that takes no parameters and returns a SomeType.

One of the most interesting grammars of any programming languages.

Three of these things belong together, and two are something altogether different...

SomeType t = u; SomeType t(u); SomeType t(); SomeType t; SomeType t(SomeType(u)); 

All but the third and fifth define a SomeType object on the stack and initialize it (with u in the first two case, and the default constructor in the fourth. The third is declaring a function that takes no parameters and returns a SomeType. The fifth is similarly declaring a function that takes one parameter by value of type SomeType named u.