class Concurrent::Map

def [](key)

Experimental RBS support (using type sampling data from the type_fusion project). 

type Concurrent__Map_[]_key = String | Symbol | Integer | Thread | Array[] | Array[Symbol] | nil | Hash
type Concurrent__Map_[]_return_value = ActiveRecord::ConnectionAdapters::PoolManager | ActiveSupport::Inflector::Inflections | String | Concurrent::Map | ActiveRecord::ConnectionAdapters::PostgreSQLAdapter | nil | ActionView::Template | ActionView::TemplateDetails::Requested | AASM::Base | AASM::StateMachine | AASM::StateMachineStore | ActiveRecord::ConnectionAdapters::SQLite3Adapter | Array[ActiveSupport::Notifications::Fanout::Subscribers::Evented] | Array[] | Array[Symbol] | bool

def []: (Concurrent__Map_[]_key key) -> Concurrent__Map_[]_return_value

This signature was generated using 2742 samples from 8 applications.

Returns:
  • (Object) - the value

Parameters:
  • key (Object) -- 
def [](key)
  if value = super # non-falsy value is an existing mapping, return it right away
    value
    # re-check is done with get_or_default(key, NULL) instead of a simple !key?(key) in order to avoid a race condition, whereby by the time the current thread gets to the key?(key) call
    # a key => value mapping might have already been created by a different thread (key?(key) would then return true, this elsif branch wouldn't be taken and an incorrent +nil+ value
    # would be returned)
    # note: nil == value check is not technically necessary
  elsif @default_proc && nil == value && NULL == (value = get_or_default(key, NULL))
    @default_proc.call(self, key)
  else
    value
  end
end