为什么在go中分配对结构的引用？

Question

I'm having a look at the code at this page:

http://golang.org/pkg/net/http/

And there's one thing I don't understand - at some point, a new structure is created and initialized like this:

client := &http.Client{
    CheckRedirect: redirectPolicyFunc,
}

Why use & when creating this structure?

I've also read this blog post and structs are initialized like this:

r := Rectangle{}

What is the difference between both and how should I know which one to use?

Answer 1

The difference is in the type of your variable.

client := &http.Client{

makes client of type *http.Client

while

client := http.Client{

builds a http.Client.