Method: Concurrent::Map#fetch_or_store

Defined in:
lib/concurrent-ruby/concurrent/map.rb

#fetch_or_store(key, default_value = NULL) {|key| ... } ⇒ Object

Fetch value with key, or store default value when key is absent, or fail when no default_value is given. This is a two step operation, therefore not atomic. The store can overwrite other concurrently stored value.

Parameters:

  • key (Object)
  • default_value (Object) (defaults to: NULL)

Yields:

  • default value for a key

Yield Parameters:

  • key (Object)

Yield Returns:

  • (Object) —

    default value

Returns:

  • (Object) —

    the value or default value



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# File 'lib/concurrent-ruby/concurrent/map.rb', line 205

def fetch_or_store(key, default_value = NULL)
  fetch(key) do
    put(key, block_given? ? yield(key) : (NULL == default_value ? raise_fetch_no_key : default_value))
  end
end