Struct

A struct in Go is a data structure that is composed of fields, where each field has a type. Here is what a Go struct looks like:

type myStruct struct{
    intField int
    stringField string
    sliceField []int
}

The preceding code creates a struct type that is called myStruct, which contains three fields:

• intField of type int
• stringField of type string
• sliceField of type []int

You can then initialize and use that struct type in your code:

var s = myStruct{
intField: 3,
stringField: "three",
sliceField : []int{1,2,3},
}

The preceding method of initialization is also known as struct literals. There is a shorter version of it that looks like this:

var s = myStruct{3,"three",[]int{1,2,3}}

You can also use what is known as dot notation, which looks as follows:

var s = myStruct{}
s.intField = 3
s.stringField = "three"
s.sliceField= []int{1,2,3}

You can obtain a pointer to a struct by doing this:

var sPtr = &myStruct{
intField:3,
stringField:"three",
sliceField: []int{1,2,3},
}

A dot notation can be used with a Go struct pointer, since Go will understand what needs to be done without the need to do any pointer de-referencing:

var s = &myStruct{}
s.intField = 3
s.stringField = "three"
s.sliceField= []int{1,2,3}

If the Go struct field names start with lower case letters, they will not be visible to external packages. If you want your struct or its fields to be visible to other packages, start the struct and/or field name with upper case letters.

Now, let's talk about Go methods.