Class: Concurrent::LockFreeStack

Inherits:
Synchronization::Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb

Overview

Note:

Edge Features are under active development and may change frequently.

  • Deprecations are not added before incompatible changes.
  • Edge version: major is always 0, minor bump means incompatible change, patch bump means compatible change.
  • Edge features may also lack tests and documentation.
  • Features developed in concurrent-ruby-edge are expected to move to concurrent-ruby when finalised.

Defined Under Namespace

Classes: Node

Constant Summary collapse

EMPTY =

The singleton for empty node

Node[nil, nil]

Instance Method Summary collapse

Constructor Details

#initialize(head = EMPTY) ⇒ LockFreeStack

Returns a new instance of LockFreeStack.

Parameters:

  • head (Node) (defaults to: EMPTY) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 51 def initialize(head = EMPTY) super() self.head = head end

Instance Method Details

#clear ⇒ true, false

Returns:

  • (true, false) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 118 def clear while true current_head = head return false if current_head == EMPTY return true if compare_and_set_head current_head, EMPTY end end

#clear_each {|value| ... } ⇒ self

Yields:

  • over the cleared stack

Yield Parameters:

  • value (Object)

Returns:

  • (self) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 142 def clear_each(&block) while true current_head = head return self if current_head == EMPTY if compare_and_set_head current_head, EMPTY each current_head, &block return self end end end

#clear_if(head) ⇒ true, false

Parameters:

Returns:

  • (true, false) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 128 def clear_if(head) compare_and_set_head head, EMPTY end

#compare_and_clear(head) ⇒ true, false

Parameters:

Returns:

  • (true, false) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 99 def compare_and_clear(head) compare_and_set_head head, EMPTY end

#compare_and_pop(head) ⇒ true, false

Parameters:

Returns:

  • (true, false) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 85 def compare_and_pop(head) compare_and_set_head head, head.next_node end

#compare_and_push(head, value) ⇒ true, false

Parameters:

  • head (Node)
  • value (Object)

Returns:

  • (true, false) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 65 def compare_and_push(head, value) compare_and_set_head head, Node[value, head] end

#each(head = nil) ⇒ self

Parameters:

  • head (Node) (defaults to: nil)

Returns:

  • (self) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 107 def each(head = nil) return to_enum(:each, head) unless block_given? it = head || peek until it.equal?(EMPTY) yield it.value it = it.next_node end self end

#empty?(head = head()) ⇒ true, false

Parameters:

  • head (Node) (defaults to: head())

Returns:

  • (true, false) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 58 def empty?(head = head()) head.equal? EMPTY end

#peek ⇒ Node

Returns:

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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 79 def peek head end

#pop ⇒ Object

Returns:

  • (Object) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 90 def pop while true current_head = head return current_head.value if compare_and_set_head current_head, current_head.next_node end end

#push(value) ⇒ self

Parameters:

  • value (Object)

Returns:

  • (self) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 71 def push(value) while true current_head = head return self if compare_and_set_head current_head, Node[value, current_head] end end

#replace_if(head, new_head) ⇒ true, false

Parameters:

Returns:

  • (true, false) 
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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 135 def replace_if(head, new_head) compare_and_set_head head, new_head end

#to_s ⇒ String Also known as: inspect

Returns Short string representation.

Returns:

  • (String) —

    Short string representation.

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# File 'lib/concurrent-ruby/concurrent/collection/lock_free_stack.rb', line 154 def to_s format '%s %s>', super[0..-2], to_a.to_s end