Language Reference: None

Pointless includes a value none which is used to represent values that aren't defined or which can't be calculated.

See the standard library None module for built-in functions for working with none values.

Syntax

In Pointless, the none value is accessible through the none keyword.

none

none

As a Placeholder Value

Using none to represent a value that is not defined:

-- Define `state` as `none` for a city that has no state
{ city: "Washington", state: none, population: 702250 }

{ city: "Washington", state: none, population: 702250 }

Using none to represent a value that cannot be calculated:

-- Get the first item in `list`, or `none` if list is empty
fn first(list)
  if isEmpty(list) then
    none
  else
    list[0]
  end
end

first(["a", "b", "c", "d"])
first([])

"a"
none

In Language Constructs

Sometimes language constructs will produce none values. For example, a function that contains no code will return none when called.

fn nada()
end

nada()

none

You can find more information on situations where language produces none values in the other chapters of the language reference.