Function declaration syntax in Go

Question

What is (c App) in the following function declaration?

func (c App) SaveSettings(setting string) revel.Result {
--------------------------------------------------------------------------------------
func                                                      Keyword to define a function
     (c App)                                              ????
             SaveSettings                                 Function name
                         (setting string)                 Function arguments
                                          revel.Result    Return type

Instead of asking such questions I'd suggest skimming the short and easy to find Go Language Specification. IMO, questions and answers that do nothing more than just regurgitate parts of a readily available and more authoritative source aren't useful. — Dave C
– Dave C, Commented Jul 23, 2015 at 19:24
1) I wouldn't say that document is short at all. 2) I already looked at that document, but I was looking at function declarations, not method declarations, because I know nothing about Go: golang.org/ref/spec#Function_declarations 3) Actually everything can be found in more authoritative sources. I think this question may be of use to future people learning Go, and perfectly fits on Stack Overflow. — Ivan
– Ivan, Commented Jul 23, 2015 at 19:33
@Ivan, agreed, I was looking at Function_declarations too! And the doc isn't short. — stackoverflower
– stackoverflower, Commented Feb 22, 2017 at 18:34

twotwotwo · Accepted Answer · 2015-07-23 18:50:17Z

14

(c App) gives the name and type of the receiver, Go's equivalent of C++ or JavaScript's this or Python's self. c is the receiver's name here, since in Go it's conventional to use a short, context-sensitive name instead of something generic like this. See http://golang.org/ref/spec#Method_declarations --

A method is a function with a receiver. The receiver is specified via an extra parameter section preceeding the method name.

and its example:

func (p *Point) Length() float64 {
    return math.Sqrt(p.x * p.x + p.y * p.y)
}

answered Jul 23, 2015 at 18:50

twotwotwo

30.4k8 gold badges72 silver badges60 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Function declaration syntax in Go

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related