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# encoding: utf-8
# typed: strict
# frozen_string_literal: true
# utilities.rb : General-purpose utility classes which don't fit anywhere else
#
# Copyright August 2012, Alex Dowad. All Rights Reserved.
#
# This is free software. Please see the LICENSE and COPYING files for details.
#
# This was originally written for the prawn gem.
require 'thread'
class PDF::Reader
# Throughout the pdf-reader codebase, repeated calculations which can benefit
# from caching are made In some cases, caching and reusing results can not
# only save CPU cycles but also greatly reduce memory requirements But at the
# same time, we don't want to throw away thread safety We have two
# interchangeable thread-safe cache implementations:
class SynchronizedCache
#: () -> void
def initialize
@cache = {} #: Hash[Object, untyped]
@mutex = Mutex.new #: Mutex
end
#: (Object) -> untyped
def [](key)
@mutex.synchronize { @cache[key] }
end
#: (Object, (Object | nil)) -> untyped
def []=(key,value)
@mutex.synchronize { @cache[key] = value }
end
end
end
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