Nvir.Cast (Nvir v0.13.2)

Collection of casters for environment variables.

Summary

Types

caster()

result()

Functions

cast(value, caster)

Casts the given value to the desired type.

Types

caster()

@type caster() ::
  :string
  | :string?
  | :string!
  | :atom
  | :atom?
  | :atom!
  | :existing_atom
  | :existing_atom?
  | :existing_atom!
  | :boolean
  | :boolean!
  | :boolean?
  | :integer!
  | :integer?
  | :integer
  | :float!
  | :float?
  | :float
  | (term() -> result())

result()

@type result() ::
  {:ok, term()} | {:error, String.t()} | {:error, :empty} | {:error, :bad_cast}

Functions

cast(value, caster)

@spec cast(term(), caster()) :: result()

@spec cast(String.t(), caster()) :: result()

Casts the given value to the desired type.

Environment variables are always defined as a string. Thus, the cast/2 function will only accept strings for the value argument.

Accepts a built-in caster or a custom function returning {:ok, value} or {:error, String.t()}. You may as well directly return an error tuple from a recursive cast/2 call.

The list of built-in casters is described in the reading environment variables guide.