Go Notes: Types

Intro

Go has many built in types that are found in other programming languages. It also supports the creation of custom types.

Each type has a default zero value that is used when a variable is declared but not yet assigned a value.

Boolean

Booleans are true or false values. The zero value for a boolean is false .

// Declare a boolean with its zero value

var stuff bool // false

// Declare a boolean and set its value

things := true

Integer

Go supports a number of both of signed and unsigned integer types. They range in from one to four bytes in size.

The default zero value for all integer types is 0

A byte is an alias for uint8. In practice byte is preferred over uint8

On a 32-bit CPU an int/uint is an int32/uint32. On most 64-bit CPU's an int/uint is an int64/uint64

The most common integer types are listed below.

Float

Go supports two types of floats; float32 and float64

The default zero value for a float is 0

Strings

Strings in Go are represented with the double quote characters "" .

The default zero value for a string is an empty string "" .

Strings in Go are immutable, once they are assigned the value cannot be changed.

Considerations

• Go does not have any automatic type promotion/conversion
• If required, types must be explicitly converted
• There are no truthy/falsy values in Go