class Channel(T)

Overview

A Channel enables concurrent communication between fibers.

They allow communicating data between fibers without sharing memory and without having to worry about locks, semaphores or other special structures.

channel = Channel(Int32).new

spawn do
  channel.send(0)
  channel.send(1)
end

channel.receive # => 0
channel.receive # => 1

Defined in:

channel.cr

Constructors

Class Method Summary

Instance Method Summary

Instance methods inherited from class Reference

==(other : self)
==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference)
same?(other : Nil) same?, to_s(io : IO) : Nil to_s

Constructor methods inherited from class Reference

new new

Instance methods inherited from class Object

!=(other) !=, !~(other) !~, ==(other) ==, ===(other : JSON::Any)
===(other : YAML::Any)
===(other) ===, =~(other) =~, class class, dup dup, hash(hasher)
hash hash, inspect(io : IO) : Nil
inspect : String inspect, itself itself, not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, tap(&block) tap, to_json(io : IO)
to_json to_json, to_pretty_json(indent : String = " ")
to_pretty_json(io : IO, indent : String = " ") to_pretty_json, to_s : String
to_s(io : IO) : Nil to_s, to_yaml(io : IO)
to_yaml to_yaml, try(&block) try, unsafe_as(type : T.class) forall T unsafe_as

Constructor methods inherited from class Object

from_json(string_or_io, root : String) : self
from_json(string_or_io) : self from_json, from_yaml(string_or_io : String | IO) : self from_yaml

Constructor Detail

def self.new(capacity = 0) #

[View source]

Class Method Detail

def self.receive_first(channels : Tuple | Array) #

[View source]
def self.receive_first(*channels) #

[View source]
def self.select(ops : Indexable(SelectAction), has_else = false) #

[View source]
def self.select(*ops : SelectAction) #

[View source]
def self.send_first(value, channels : Tuple | Array) #

[View source]
def self.send_first(value, *channels) #

[View source]

Instance Method Detail

def close #

[View source]
def closed? #

[View source]
def inspect(io : IO) : Nil #
Description copied from class Reference

Appends a String representation of this object which includes its class name, its object address and the values of all instance variables.

class Person
  def initialize(@name : String, @age : Int32)
  end
end

Person.new("John", 32).inspect # => #<Person:0x10fd31f20 @name="John", @age=32>

[View source]
def pretty_print(pp) #

[View source]
def receive #

Receives a value from the channel. If there is a value waiting, it is returned immediately. Otherwise, this method blocks until a value is sent to the channel.

Raises ClosedError if the channel is closed or closes while waiting for receive.

channel = Channel(Int32).new
channel.send(1)
channel.receive # => 1

[View source]
def receive? #

Receives a value from the channel. If there is a value waiting, it is returned immediately. Otherwise, this method blocks until a value is sent to the channel.

Returns nil if the channel is closed or closes while waiting for receive.


[View source]
def receive_impl(&block) #

[View source]
def receive_internal(&block) #

[View source]
def send(value : T) #

[View source]