Contents

# frozen_string_literal: true

module KO
  module Signals
    class Signal
      attr_reader :name, :arg_types, :connections

      def initialize(name, arg_types)
        @name = name
        @arg_types = arg_types

        @validator = Validator.new(self)
        @connections = {}
      end

      def dup = super().tap { _1.connections.clear }

      def receiver_name = "on_#{name}".to_sym

      # Only 3 ways to connect:
      # some_object.some_signal.connect(receiver) -> receiver#on_some_signal
      # some_object.some_signal.connect(receiver.method(:do_something)) -> receiver#do_something
      # some_object.some_signal.connect(receiver.another_signal) ->  emits receiver#another_signal
      # Blocks, Procs and Lambda are not supported on purpose
      def connect(callable = nil, mode: :direct, one_shot: false)
        @validator.validate_callable!(callable)

        Connection.new(callable, self, mode:, one_shot:).tap { @connections[callable] = _1 }
      end

      def disconnect(callable)
        raise ArgumentError, "given callable is not connected to this signal" if @connections.delete(callable).nil?
      end

      def emit(*args)
        @validator.validate_args!(args)
        notify_subscribers(args)
      end

      def inspect = "#<#{self.class}[#{name.inspect}] connections=#{@connections.count}>"

      def call(...) = emit(...)

      def notify_subscribers(args)
        @connections.values.shuffle.each do |connection|
          connection.call(*args)
        ensure
          connection.disconnect if connection.one_shot?
        end
      end
    end
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
ko-0.1.2	lib/ko/signals/signal.rb