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bookMap Declaration and Initialization

We can declare an empty map using the make() function. Below is the syntax we need to follow:

var mapName = make(map[keyType]valueType)
// or
mapName := make(map[keyType]valueType)

Here, mapName is the name of the map, keyType is the expected type of the keys, and valueType is the expected type of the values. The term map is a keyword.

We can declare a map called courseData with keys of type string and values of type int.

index.go

index.go

copy

              
1

            
var courseData = make(map[string]int)

If we attempt to output this map, we will receive an output indicating an empty map:

index.

index.

copy

              
1

            
fmt.Println(courseData) // Output: map[]

We can initialize a map with some data using the following syntax:

var mapName = map[keyType]valueType = {
    key1: value1,    
    key2: value2,
    key3: value 3,
    …
}

Note

You can place or omit spaces in the map declaration syntax; therefore, both map[keyType]valueType and map [keyType] valueType are valid.

Using the above syntax, we can create a map that has some initial data in it:

index.go

index.go

copy

              
1234567

            
myMap := map[string]int {
	"a": 10,
	"b": 11,
	"c": 12,
}

fmt.Println(myMap) // Output: map[a:10 b:11 c:12]
question mark

Which syntax is correct for creating a new empty map?

Select the correct answer

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Come possiamo migliorarlo?

Grazie per i tuoi commenti!

Sezione 6. Capitolo 5

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bookMap Declaration and Initialization

Scorri per mostrare il menu

We can declare an empty map using the make() function. Below is the syntax we need to follow:

var mapName = make(map[keyType]valueType)
// or
mapName := make(map[keyType]valueType)

Here, mapName is the name of the map, keyType is the expected type of the keys, and valueType is the expected type of the values. The term map is a keyword.

We can declare a map called courseData with keys of type string and values of type int.

index.go

index.go

copy

              
1

            
var courseData = make(map[string]int)

If we attempt to output this map, we will receive an output indicating an empty map:

index.

index.

copy

              
1

            
fmt.Println(courseData) // Output: map[]

We can initialize a map with some data using the following syntax:

var mapName = map[keyType]valueType = {
    key1: value1,    
    key2: value2,
    key3: value 3,
    …
}

Note

You can place or omit spaces in the map declaration syntax; therefore, both map[keyType]valueType and map [keyType] valueType are valid.

Using the above syntax, we can create a map that has some initial data in it:

index.go

index.go

copy

              
1234567

            
myMap := map[string]int {
	"a": 10,
	"b": 11,
	"c": 12,
}

fmt.Println(myMap) // Output: map[a:10 b:11 c:12]
question mark

Which syntax is correct for creating a new empty map?

Select the correct answer

Tutto è chiaro?

Come possiamo migliorarlo?

Grazie per i tuoi commenti!

Sezione 6. Capitolo 5
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