Method within selectors

September 1, 2023

Method declarations

The method is said to be bound to its receiver base type and the method name is visible only within selectors for type T or *T.

This short sentence is a bit tricky to parse, because it relies on some as-yet unfamilar concepts. But it’s really pretty straight forward once those concepts are understood.

A selector expression looks something like So given the following type and method:

type foo int

func (f foo) bar() {}

the method bar is bound to the receiver base type foo, and the method name is only visible within selectors for foo or *foo. All other references to bar do not refer to this method.

So to further expand the example to illustrate:

var x foo // A valid selector expression. x is of type `foo`, so `bar` refernces the method on `foo`

var y *foo // Also valid, y is of type `*foo`

var z int // Invalid. z is of type int, which has no method `bar` bound to it.

Quotes from The Go Programming Language Specification Version of August 2, 2023

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