What does this syntax mean?

[Giuseppe:G:]

Hi, the following piece of code is rather obscure for me

struct Foo
{
Foo( int _x ) : x(_x) {}
....
};

what's the meaning of that construct? I understand Foo() must be a
constructor, right? But then what's with the syntax after the ":" ??

Thanks!
Giuseppe

 

[Ian Collins]

Hi, the following piece of code is rather obscure for me

struct Foo
{
Foo( int _x ) : x(_x) {}
....
};

what's the meaning of that construct? I understand Foo() must be a
constructor, right? But then what's with the syntax after the ":" ??

Look up initialiser lists.

 

[David Côme]

Hi, the following piece of code is rather obscure for me

struct Foo
{
Foo( int _x ) : x(_x) {}
...
};

what's the meaning of that construct? I understand Foo() must be a
constructor, right? But then what's with the syntax after the ":" ??

Thanks!
Giuseppe

Search "initialization lists" on google.

 

[Tim Slattery]

Hi, the following piece of code is rather obscure for me

struct Foo
{
Foo( int _x ) : x(_x) {}
...
};

Foo takes an integer argument. the :x(_x) says to initialize the
member variable x using the argument _x. "{}" says that the body of
the method is empty, that is, the initialization is the only thing
that the constructor does.