Struct nil 

pub struct nil;

The type of the absence of a value.

nil has a single value, also called nil, whose main property is to be different from every other value. It usually represents a missing or deleted value: assigning nil to a table field removes that field, and reading a variable that was never assigned yields nil.

In a condition, nil (together with false) counts as false; every other value counts as true.

Trait Implementations

impl tostring for nil

fn __tostring(&self) -> string

Invoked by tostring() (and therefore by print) to convert the value to a string.

fn __name(&self) -> string

A string naming the type of the value, used in error messages and by tostring when __tostring is absent.