View Source Reactor.Dsl.Argument (reactor v0.8.5)

The struct used to store argument DSL entities.

See Reactor.step.argument.

Summary

Types

t()

Functions

input(input_name, sub_path \\ [])

The input template helper for the Reactor DSL.

result(step_name, sub_path \\ [])

The result template helper for the Reactor DSL.

value(value)

The value template helper for the Reactor DSL.

Types

t()

@type t() :: %Reactor.Dsl.Argument{
  __identifier__: any(),
  name: atom(),
  source: Reactor.Template.t(),
  transform: nil | (any() -> any()) | {module(), keyword()} | mfa()
}

Functions

input(input_name, sub_path \\ [])

@spec input(atom(), [any()]) :: Reactor.Template.Input.t()

The input template helper for the Reactor DSL.

Example

defmodule ExampleReactor do
  use Reactor

  input :name

  step :greet do
    # here: --------↓↓↓↓↓
    argument :name, input(:name)
    run fn
      %{name: nil}, _, _ -> {:ok, "Hello, World!"}
      %{name: name}, _, _ -> {:ok, "Hello, #{name}!"}
    end
  end
end

Extracting nested values

You can provide a list of keys to extract from a data structure, similar to Kernel.get_in/2 with the condition that the input value is either a struct or implements the Access protocol.

result(step_name, sub_path \\ [])

@spec result(atom(), [any()]) :: Reactor.Template.Result.t()

The result template helper for the Reactor DSL.

Example

defmodule ExampleReactor do
  use Reactor

  step :whom do
    run fn ->
      {:ok, Enum.random(["Marty", "Doc", "Jennifer", "Lorraine", "George", nil])}
    end
  end

  step :greet do
    # here: --------↓↓↓↓↓↓
    argument :name, result(:whom)
    run fn
      %{name: nil}, _, _ -> {:ok, "Hello, World!"}
      %{name: name}, _, _ -> {:ok, "Hello, #{name}!"}
    end
  end
end

Extracting nested values

You can provide a list of keys to extract from a data structure, similar to Kernel.get_in/2 with the condition that the result is either a struct or implements the Access protocol.

value(value)

@spec value(any()) :: Reactor.Template.Value.t()

The value template helper for the Reactor DSL.

Example

defmodule ExampleReactor do
  use Reactor

  input :number

  step :times_three do
    argument :lhs, input(:number)
    # here: -------↓↓↓↓↓
    argument :rhs, value(3)

    run fn args, _, _ ->
      {:ok, args.lhs * args.rhs}
    end
  end
end