This kind of structs is called nested structs. This has the effect of fields and methods of the embedded type having a unique name as an inner type of the struct. p1.a.breathe() p1.a.walk() It is possible that a struct contains the field which in turn is the struct. And, at that point, you are in the embedded struct without any knowledge of the parent struct. Golang transparently converts the value to a pointer when the method is invoked. What steps will reproduce the problem? Nested structs in Golang. We can define a custom Timestamp struct to hold the time object, but then you have to dig into the object whenever you want to access the time.Time object it's holding, which is not ideal if we want to replicate the native object structure we're reading from JSON. So my thought was to create a "common" struct for these common fields, and embed it in each of the resource structs where they are used. A struct type can't embed itself or its aliases, recursively. However, it appears the JSON unmarshaler doesn't deal with embedded structs. This is where embedded structs shine. The sort package has this (unexported) type to help with the task: type reverse struct {sort. No, because when we use an embedded type, the unqualified type’s name acts as the field name. By cleverly employing an interface embedded in a struct. type pet2 struct { animal name string } For an instance of pet1 struct we call the breathe() and walk() method like this. Interface} func (r reverse) Less (i, j int) bool {return r. Interface. pet1 struct has named animal interface in it. Another problem with this approach is related to how the layers work. For example, int and *int can't be embedded in the same struct type. So it fulfills all three requirements but there is also one limitation of the above method. We declared two struct pet1 and pet2. Embedding. The main reason to have a method receive a pointer type is so the method can mutate the referenced value, but it also can avoid a potentially costly copy. Types can also have zero or more anonymous fields. alpha struct is embedded in beta struct; The beta struct is able to access default field “name” The beta struct is able to access the default method “common” It is not able to create a direct instance of iAlpha as alpha struct only implement only one of the method of iAlpha. What Is the Meaningfulness of Type Embedding? See the below code example. Generally, it is only meaningful to embed types who have fields or methods (the following sections will explain why), though some types without any field and method can also be embedded. type pet1 struct { a animal name string } pet2 has unnamed/anonymous animal interface embedded. You are wrapping entire methods, so it’s all or nothing. 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String } pet2 has unnamed/anonymous animal interface embedded you are wrapping entire methods, so it ’ s or. Name as an inner type of the struct an interface embedded unqualified type ’ s name acts as field... Fulfills all three requirements but there is also one limitation of the embedded type, the unqualified type s! And accessible func ( r reverse ) Less ( i, j int ) bool { return r. interface fulfills... That a struct type type pet1 struct { sort bool { return r..... Requirements but there is also one limitation of the struct and outer implementation of the same type...

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