Golang: Basic Types

Basic Types

Go's basic types are

Boolean:

• bool (possible values are true and false)

String:

• string

Signed integer types:

• int
• int8
• int16
• int32
• int64

Unsigned Integer types:

• uint
• uint8 alias byte 〔see What is Byte〕
• uint16
• uint32 alias rune, represents a Unicode Codepoint. 〔see Golang: Rune〕
• uint64

Type to represent pointer address. 〔see Golang: Pointer〕

• uintptr

Float type. (uses decimal notation, to represent approximation of Real Numbers)

• float32
• float64

Complex numbers type:

• complex64
• complex128

The int, uint, and uintptr types are usually 32 bits wide on 32-bit systems and 64 bits wide on 64-bit systems.

Find a Value's Type

fmt.Printf("%T\n", val)

Print a value's type.

package main

import "fmt"

func main() {

	var nn = 3
	var ff = 3.123

	// print their types
	fmt.Printf("%T\n", nn) // int
	fmt.Printf("%T\n", ff) // float64
}

Type conversions

type(v)

Converts the value v to the type type, where type is the same keyword as the type declaration.

e.g. float64(3) convert value 3 to float64 type.

package main

import (
	"fmt"
	"reflect"
)

func main() {
	var i int = 42
	var f = float64(i)
	fmt.Println(reflect.TypeOf(f)) // float64

}