Add bin and edit workflow

bin/gems/kramdown-2.5.1/lib/kramdown/utils/lru_cache.rb

@@ -0,0 +1,41 @@
+# -*- coding: utf-8; frozen_string_literal: true -*-
+#
+#--
+# Copyright (C) 2009-2019 Thomas Leitner <t_leitner@gmx.at>
+#
+# This file is part of kramdown which is licensed under the MIT.
+#++
+#
+
+module Kramdown
+  module Utils
+
+    # A simple least recently used (LRU) cache.
+    #
+    # The cache relies on the fact that Ruby's Hash class maintains insertion order. So deleting
+    # and re-inserting a key-value pair on access moves the key to the last position. When an
+    # entry is added and the cache is full, the first entry is removed.
+    class LRUCache
+
+      # Creates a new LRUCache that can hold +size+ entries.
+      def initialize(size)
+        @size = size
+        @cache = {}
+      end
+
+      # Returns the stored value for +key+ or +nil+ if no value was stored under the key.
+      def [](key)
+        (val = @cache.delete(key)).nil? ? nil : @cache[key] = val
+      end
+
+      # Stores the +value+ under the +key+.
+      def []=(key, value)
+        @cache.delete(key)
+        @cache[key] = value
+        @cache.shift if @cache.length > @size
+      end
+
+    end
+
+  end
+end