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##
# Hash
#
# ISO 15.2.13
class Hash
##
# Equality---Two hashes are equal if they each contain the same number
# of keys and if each key-value pair is equal to (according to
# <code>Object#==</code>) the corresponding elements in the other
# hash.
#
# ISO 15.2.13.4.1
def ==(hash)
return true if self.equal?(hash)
begin
hash = hash.to_hash
rescue NoMethodError
return false
end
return false if self.size != hash.size
self.each do |k,v|
return false unless hash.key?(k)
return false unless self[k] == hash[k]
end
return true
end
##
# Returns <code>true</code> if <i>hash</i> and <i>other</i> are
# both hashes with the same content compared by eql?.
#
# ISO 15.2.13.4.32 (x)
def eql?(hash)
return true if self.equal?(hash)
begin
hash = hash.to_hash
rescue NoMethodError
return false
end
return false if self.size != hash.size
self.each do |k,v|
return false unless hash.key?(k)
return false unless self[k].eql?(hash[k])
end
return true
end
##
# Delete the element with the key +key+.
# Return the value of the element if +key+
# was found. Return nil if nothing was
# found. If a block is given, call the
# block with the value of the element.
#
# ISO 15.2.13.4.8
def delete(key, &block)
if block && !self.has_key?(key)
block.call(key)
else
self.__delete(key)
end
end
##
# Calls the given block for each element of +self+
# and pass the key and value of each element.
#
# call-seq:
# hsh.each {| key, value | block } -> hsh
# hsh.each_pair {| key, value | block } -> hsh
# hsh.each -> an_enumerator
# hsh.each_pair -> an_enumerator
#
#
# If no block is given, an enumerator is returned instead.
#
# h = { "a" => 100, "b" => 200 }
# h.each {|key, value| puts "#{key} is #{value}" }
#
# <em>produces:</em>
#
# a is 100
# b is 200
#
# ISO 15.2.13.4.9
def each(&block)
return to_enum :each unless block
keys = self.keys
vals = self.values
len = self.size
i = 0
while i < len
block.call [keys[i], vals[i]]
i += 1
end
self
end
##
# Calls the given block for each element of +self+
# and pass the key of each element.
#
# call-seq:
# hsh.each_key {| key | block } -> hsh
# hsh.each_key -> an_enumerator
#
# If no block is given, an enumerator is returned instead.
#
# h = { "a" => 100, "b" => 200 }
# h.each_key {|key| puts key }
#
# <em>produces:</em>
#
# a
# b
#
# ISO 15.2.13.4.10
def each_key(&block)
return to_enum :each_key unless block
self.keys.each{|k| block.call(k)}
self
end
##
# Calls the given block for each element of +self+
# and pass the value of each element.
#
# call-seq:
# hsh.each_value {| value | block } -> hsh
# hsh.each_value -> an_enumerator
#
# If no block is given, an enumerator is returned instead.
#
# h = { "a" => 100, "b" => 200 }
# h.each_value {|value| puts value }
#
# <em>produces:</em>
#
# 100
# 200
#
# ISO 15.2.13.4.11
def each_value(&block)
return to_enum :each_value unless block
self.keys.each{|k| block.call(self[k])}
self
end
##
# Replaces the contents of <i>hsh</i> with the contents of other hash
#
# ISO 15.2.13.4.23
def replace(hash)
raise TypeError, "can't convert argument into Hash" unless hash.respond_to?(:to_hash)
self.clear
hash = hash.to_hash
hash.each_key{|k|
self[k] = hash[k]
}
if hash.default_proc
self.default_proc = hash.default_proc
else
self.default = hash.default
end
self
end
# ISO 15.2.13.4.17
alias initialize_copy replace
##
# Return a hash which contains the content of
# +self+ and +other+. If a block is given
# it will be called for each element with
# a duplicate key. The value of the block
# will be the final value of this element.
#
# ISO 15.2.13.4.22
def merge(other, &block)
h = {}
raise TypeError, "can't convert argument into Hash" unless other.respond_to?(:to_hash)
other = other.to_hash
self.each_key{|k| h[k] = self[k]}
if block
other.each_key{|k|
h[k] = (self.has_key?(k))? block.call(k, self[k], other[k]): other[k]
}
else
other.each_key{|k| h[k] = other[k]}
end
h
end
# internal method for Hash inspection
def _inspect
return "{}" if self.size == 0
"{"+self.map {|k,v|
k._inspect + "=>" + v._inspect
}.join(", ")+"}"
end
##
# Return the contents of this hash as a string.
#
# ISO 15.2.13.4.30 (x)
def inspect
begin
self._inspect
rescue SystemStackError
"{...}"
end
end
# ISO 15.2.13.4.31 (x)
alias to_s inspect
##
# call-seq:
# hsh.reject! {| key, value | block } -> hsh or nil
# hsh.reject! -> an_enumerator
#
# Equivalent to <code>Hash#delete_if</code>, but returns
# <code>nil</code> if no changes were made.
#
# 1.8/1.9 Hash#reject! returns Hash; ISO says nothing.
#
def reject!(&block)
return to_enum :reject! unless block
keys = []
self.each{|k,v|
if block.call([k, v])
keys.push(k)
end
}
return nil if keys.size == 0
keys.each{|k|
self.delete(k)
}
self
end
##
# call-seq:
# hsh.reject {|key, value| block} -> a_hash
# hsh.reject -> an_enumerator
#
# Returns a new hash consisting of entries for which the block returns false.
#
# If no block is given, an enumerator is returned instead.
#
# h = { "a" => 100, "b" => 200, "c" => 300 }
# h.reject {|k,v| k < "b"} #=> {"b" => 200, "c" => 300}
# h.reject {|k,v| v > 100} #=> {"a" => 100}
#
# 1.8/1.9 Hash#reject returns Hash; ISO says nothing.
#
def reject(&block)
return to_enum :reject unless block
h = {}
self.each{|k,v|
unless block.call([k, v])
h[k] = v
end
}
h
end
##
# call-seq:
# hsh.select! {| key, value | block } -> hsh or nil
# hsh.select! -> an_enumerator
#
# Equivalent to <code>Hash#keep_if</code>, but returns
# <code>nil</code> if no changes were made.
#
# 1.9 Hash#select! returns Hash; ISO says nothing.
#
def select!(&block)
return to_enum :select! unless block
keys = []
self.each{|k,v|
unless block.call([k, v])
keys.push(k)
end
}
return nil if keys.size == 0
keys.each{|k|
self.delete(k)
}
self
end
##
# call-seq:
# hsh.select {|key, value| block} -> a_hash
# hsh.select -> an_enumerator
#
# Returns a new hash consisting of entries for which the block returns true.
#
# If no block is given, an enumerator is returned instead.
#
# h = { "a" => 100, "b" => 200, "c" => 300 }
# h.select {|k,v| k > "a"} #=> {"b" => 200, "c" => 300}
# h.select {|k,v| v < 200} #=> {"a" => 100}
#
# 1.9 Hash#select returns Hash; ISO says nothing
#
def select(&block)
return to_enum :select unless block
h = {}
self.each{|k,v|
if block.call([k, v])
h[k] = v
end
}
h
end
##
# call-seq:
# hsh.rehash -> hsh
#
# Rebuilds the hash based on the current hash values for each key. If
# values of key objects have changed since they were inserted, this
# method will reindex <i>hsh</i>.
#
# h = {"AAA" => "b"}
# h.keys[0].chop!
# h #=> {"AA"=>"b"}
# h["AA"] #=> nil
# h.rehash #=> {"AA"=>"b"}
# h["AA"] #=> "b"
#
def rehash
h = {}
self.each{|k,v|
h[k] = v
}
self.replace(h)
end
def __update(h)
h.each_key{|k| self[k] = h[k]}
self
end
end
##
# Hash is enumerable
#
# ISO 15.2.13.3
class Hash
include Enumerable
end