rubyx/lib/parfait/dictionary.rb
2015-05-20 13:50:56 +03:00

107 lines
2.9 KiB
Ruby

# almost simplest hash imaginable. make good use of Lists
module Parfait
class Dictionary < Object
# only empty initialization for now
#
# internally we store keys and values in lists, which means this does **not** scale well
def initialize
@keys = List.new_object()
@values = List.new_object()
end
# return all values as a list
# TODO, list should be copied to avoid inconcisencies
def values()
@values
end
# return all keys as a list
# TODO, list should be copied to avoid inconcisencies
def keys()
@keys
end
# are there any key/value items in the list
def empty?
@keys.empty?
end
# How many key/value pairs there are
def length()
return @keys.get_length()
end
# get a value fot the given key
# key ientity is checked with == not === (ie equals not identity)
# return nil if no such key
def get(key)
index = key_index(key)
if( index )
@values.get(index)
else
nil
end
end
# same as get(key)
def [](key)
get(key)
end
# private method
def key_index(key)
len = @keys.get_length()
index = 1
found = nil
while(index <= len)
if( @keys.get(index) == key)
found = index
break
end
index += 1
end
found
end
# set key with value, returns value
def set(key , value)
index = key_index(key)
if( index )
@keys.set(index , value)
else
@keys.push(key)
@values.push(value)
end
value
end
#same as set(k,v)
def []=(key,val)
set(key,val)
end
# yield to each key value pair
def each
index = 1
while index <= @keys.get_length
key = @keys.get(index)
value = @values.get(index)
yield key , value
index = index + 1
end
self
end
# :rehash, :to_hash, :to_h, :to_a, :[], :fetch, :[]=, :store, :default, :default=, :default_proc, :default_proc=,
# :key, :index, :size, :length, :empty?, :each_value, :each_key, :each_pair, :each, :keys, :values,
# :values_at, :shift, :delete, :delete_if, :keep_if, :select, :select!, :reject, :reject!, :clear, :invert,
# :update, :replace, :merge!, :merge, :assoc, :rassoc, :flatten, :include?, :member?, :has_key?, :has_value?,
# :key?, :value?, :compare_by_identity, :compare_by_identity?, :entries, :sort, :sort_by, :grep, :count, :find,
# :detect, :find_index, :find_all, :collect, :map, :flat_map, :collect_concat, :inject, :reduce, :partition,
# :group_by, :first, :all?, :any?, :one?, :none?, :min, :max, :minmax, :min_by, :max_by, :minmax_by, :each_with_index,
# :reverse_each, :each_entry, :each_slice, :each_cons, :each_with_object, :zip, :take, :take_while, :drop, :drop_while,
# :cycle, :chunk, :slice_before, :lazy
end
end