deterministic.rb

require 'deterministic'

module ParamDecorator
  module_function

  extend Deterministic::Prelude::Result

  # alias :>> :map
  # alias :m :method # method returns a proc for a method

  def call(params = [])
    Success(params) >> method(:parse) >> method(:validate) >> method(:finished)
  end

  def parse(params)
    params << "I parsed the params"
    Success(params)
  end

  def validate(params)
    params << "I validated the params"
    Success(params)
  end

  def finished(params)
    params << "I finished the params"
    Success(params)
  end
end

result = ParamDecorator.call

# puts result
puts result.class # Deterministic::Result::Success
puts result.value.join(' -> ') # I parsed the params -> I validated the params -> I finished the params