C ++ 11中的奇怪初始化

Question

I've heard I can initialize a value using this syntax:

int foo = {5};

Also, I can do the same thing using even less code:

int foo{5};

Well, are there any advantages/disadvantages of using them? Is it a good practice, or maybe it's better to use standard: ?

int foo = 5;

Answer 1

The three examples you gave, are not quite the same. Uniform initialization (the ones with { } ) does not allow narrowing conversions

int i = 5.0;   // Fine, stores 5
int i{5.0};    // Won't compile!
int i = {5.0}; // Won't compile!

Furthermore, copy initializations (the ones with an = ) do not allow explicit constructors.

The new C++11 feature uniform initialization and its cousin initializer-lists (which generalizes the brace initialization syntax to eg the standard containers) is a tricky animal with many quirks. The most vexing parse mentioned in the comments by @Praetorian is only one of them, tuples and multidimensional arrays are another pandora's box.