12. Integers

Using Natural Numbers

Integer Types

• Integers are used to store natural numbers are 1,2,3.

• Go has 8 types on integers

• int8, int16, int32, and int64, and corresponding unsigned versions uint8, uint16, uint32, and uint64.

• unsigned integers can store positive numbers only.

• 8,16,32 and 64 represents how many bits are used to store value.

Bits	Signed	Unsigned
8	–128 to 127	0 to 255
16	–32,768 to 32,767	0 to 65535
32	–2,147,483,648 to 2,147,483,647	0 to 4,294,967,295
64	–9,223,372,036,854,775,808 to 9,223,372,036,854,775,807	0 to 18,446,744,073,709,551,615

Declaring Integers

Integers are declared using one of the 3 ways:

main.go

var j int32 = 20
var i int = 10
var i = 10
i := 10
var k int

If we are not specifying type like in 2nd and 3rd declaration, it will default to int

Zero value for integer is 0

Always use short declaration way when assigning initial value. If you wish to initialize a variable to its zero value, use var declaration.

Using Test Driven Development for integers

Learn how to do test driven development when using integers from Chris

learn-go-with-tests/integers.md at master · quii/learn-go-with-testsGitHub