Go Notes: Types

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.

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

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.

Go supports two types of floats; float32 and float64

The default zero value for a float is 0

Note

A floating point number in Go cannot represent an exact decimal value. They should not be used for anything that requires exact decimal precision.

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.