In Files
- set.rb
Parent
Object
Methods
- ::[]
- ::new
- #&
- #+
- #-
- #<
- #<<
- #<=
- #==
- #>
- #>=
- #^
- #add
- #add?
- #classify
- #clear
- #collect!
- #delete
- #delete?
- #delete_if
- #difference
- #disjoint?
- #divide
- #each
- #empty?
- #flatten
- #flatten!
- #include?
- #initialize_copy
- #inspect
- #intersect?
- #intersection
- #keep_if
- #length
- #map!
- #member?
- #merge
- #proper_subset?
- #proper_superset?
- #reject!
- #replace
- #select!
- #size
- #subset?
- #subtract
- #superset?
- #to_a
- #to_set
- #union
- #|
Included Modules
Class/Module Index ![[+]](http://www.ruby-doc.org/./images/find.png "show/hide quicksearch")
Set
Set implements a collection of unordered values with no duplicates. This is a hybrid of Array's intuitive inter-operation facilities and Hash's fast lookup.
Set is easy to use with Enumerable objects (implementing each). Most of the initializer methods and binary operators accept generic Enumerable objects besides sets and arrays. An Enumerable object can be converted to Set using the to_set method.
Set uses Hash as storage, so you must note the following points:
Equality of elements is determined according to Object#eql? and Object#hash.
Set assumes that the identity of each element does not change while it is stored. Modifying an element of a set will render the set to an unreliable state.
When a string is to be stored, a frozen copy of the string is stored instead unless the original string is already frozen.
Comparison¶↑
The comparison operators <, >, <= and >= are implemented as shorthand for the {proper_,}{subset?,superset?} methods. However, the <=> operator is intentionally left out because not every pair of sets is comparable. ({x,y} vs. {x,z} for example)
Example¶↑
require'set's1 = Set.new [1, 2] # -> #<Set: {1, 2}>s2 = [1, 2].to_set# -> #<Set: {1, 2}>s1==s2# -> trues1.add("foo") # -> #<Set: {1, 2, "foo"}>s1.merge([2, 6]) # -> #<Set: {1, 2, "foo", 6}>s1.subset?s2# -> falses2.subset?s1# -> true
Contact¶↑
- Akinori MUSHA <knu@iDaemons.org> (current maintainer)
Public Class Methods
Creates a new set containing the given objects.
# File set.rb, line 71defself.[](*ary) new(ary) end
Creates a new set containing the elements of the given enumerable object.
If a block is given, the elements of enum are preprocessed by the given block.
# File set.rb, line 80definitialize(enum = nil, &block) # :yields: o@hash||=Hash.newenum.nil?andreturnifblockdo_with_enum(enum) { |o|add(block[o]) } elsemerge(enum) endend
Public Instance Methods
Returns a new set containing elements common to the set and the given enumerable object.
# File set.rb, line 385def&(enum) n = self.class.newdo_with_enum(enum) { |o|n.add(o) ifinclude?(o) } nend
Returns a new set built by duplicating the set, removing every element that appears in the given enumerable object.
# File set.rb, line 378def-(enum) dup.subtract(enum) end
Returns true if two sets are equal. The equality of each couple of elements is defined according to Object#eql?.
# File set.rb, line 403def==(other) ifself.equal?(other) trueelsifother.instance_of?(self.class) @hash==other.instance_variable_get(:@hash) elsifother.is_a?(Set) &&self.size==other.sizeother.all? { |o|@hash.include?(o) } elsefalseendend
Returns a new set containing elements exclusive between the set and the given enumerable object. (set ^ enum) is equivalent to ((set | enum) - (set & enum)).
# File set.rb, line 395def^(enum) n = Set.new(enum) each { |o|ifn.include?(o) thenn.delete(o) elsen.add(o) end } nend
Adds the given object to the set and returns self. Use merge to add many elements at once.
# File set.rb, line 269defadd(o) @hash[o] = trueselfend
Adds the given object to the set and returns self. If the object is already in the set, returns nil.
# File set.rb, line 277defadd?(o) ifinclude?(o) nilelseadd(o) endend
Classifies the set by the return value of the given block and returns a hash of {value => set of elements} pairs. The block is called once for each element of the set, passing the element as parameter.
e.g.:
require'set'files = Set.new(Dir.glob("*.rb")) hash = files.classify { |f|File.mtime(f).year } phash# => {2000=>#<Set: {"a.rb", "b.rb"}>,# 2001=>#<Set: {"c.rb", "d.rb", "e.rb"}>,# 2002=>#<Set: {"f.rb"}>}
# File set.rb, line 437defclassify# :yields: oblock_given?orreturnenum_for(__method__) h = {} each { |i|x = yield(i) (h[x] ||=self.class.new).add(i) } hend
Removes all elements and returns self.
# File set.rb, line 135defclear@hash.clearselfend
Replaces the elements with ones returned by collect().
# File set.rb, line 323defcollect!block_given?orreturnenum_for(__method__) set = self.class.neweach { |o|set<<yield(o) } replace(set) end
Deletes the given object from the set and returns self. Use subtract to delete many items at once.
# File set.rb, line 287defdelete(o) @hash.delete(o) selfend
Deletes the given object from the set and returns self. If the object is not in the set, returns nil.
# File set.rb, line 294defdelete?(o) ifinclude?(o) delete(o) elsenilendend
Deletes every element of the set for which block evaluates to true, and returns self.
# File set.rb, line 304defdelete_ifblock_given?orreturnenum_for(__method__) # @hash.delete_if should be faster, but using it breaks the order# of enumeration in subclasses.select { |o|yieldo }.each { |o|@hash.delete(o) } selfend
Returns true if the set and the given set have no element in common. This method is the opposite of intersect?.
# File set.rb, line 254defdisjoint?(set) !intersect?(set) end
Divides the set into a set of subsets according to the commonality defined by the given block.
If the arity of the block is 2, elements o1 and o2 are in common if block.call(o1, o2) is true. Otherwise, elements o1 and o2 are in common if block.call(o1) == block.call(o2).
e.g.:
require'set'numbers = Set[1, 3, 4, 6, 9, 10, 11] set = numbers.divide { |i,j| (i-j).abs==1 } pset# => #<Set: {#<Set: {1}>,# #<Set: {11, 9, 10}>,# #<Set: {3, 4}>,# #<Set: {6}>}>
# File set.rb, line 466defdivide(&func) funcorreturnenum_for(__method__) iffunc.arity==2require'tsort'class<<dig = {} # :nodoc:includeTSortaliastsort_each_nodeeach_keydeftsort_each_child(node, &block) fetch(node).each(&block) endendeach { |u|dig[u] = a = [] each{ |v|func.call(u, v) anda<<v } } set = Set.new() dig.each_strongly_connected_component { |css|set.add(self.class.new(css)) } setelseSet.new(classify(&func).values) endend
Calls the given block once for each element in the set, passing the element as parameter. Returns an enumerator if no block is given.
# File set.rb, line 261defeach(&block) blockorreturnenum_for(__method__) @hash.each_key(&block) selfend
Returns true if the set contains no elements.
# File set.rb, line 130defempty?@hash.empty?end
Returns a new set that is a copy of the set, flattening each containing set recursively.
# File set.rb, line 189defflattenself.class.new.flatten_merge(self) end
Equivalent to #flatten, but replaces the receiver with the result in place. Returns nil if no modifications were made.
# File set.rb, line 195defflatten!ifdetect { |e|e.is_a?(Set) } replace(flatten()) elsenilendend
Returns true if the set contains the given object.
# File set.rb, line 204definclude?(o) @hash.include?(o) end
Copy internal hash.
# File set.rb, line 104definitialize_copy(orig) @hash = orig.instance_variable_get(:@hash).dupend
Returns a string containing a human-readable representation of the set. (“#<Set: {element1, element2, …}>”)
# File set.rb, line 500definspectids = (Thread.current[InspectKey] ||= []) ifids.include?(object_id) returnsprintf('#<%s: {...}>', self.class.name) endbeginids<<object_idreturnsprintf('#<%s: {%s}>', self.class, to_a.inspect[1..-2]) ensureids.popendend
Returns true if the set and the given set have at least one element in common.
# File set.rb, line 243defintersect?(set) set.is_a?(Set) orraiseArgumentError, "value must be a set"ifsize<set.sizeany? { |o|set.include?(o) } elseset.any? { |o|include?(o) } endend
Deletes every element of the set for which block evaluates to false, and returns self.
# File set.rb, line 314defkeep_ifblock_given?orreturnenum_for(__method__) # @hash.keep_if should be faster, but using it breaks the order of# enumeration in subclasses.reject { |o|yieldo }.each { |o|@hash.delete(o) } selfend
Merges the elements of the given enumerable object to the set and returns self.
# File set.rb, line 351defmerge(enum) ifenum.instance_of?(self.class) @hash.update(enum.instance_variable_get(:@hash)) elsedo_with_enum(enum) { |o|add(o) } endselfend
Returns true if the set is a proper subset of the given set.
# File set.rb, line 234defproper_subset?(set) set.is_a?(Set) orraiseArgumentError, "value must be a set"returnfalseifset.size<=sizeall? { |o|set.include?(o) } end
Returns true if the set is a proper superset of the given set.
# File set.rb, line 218defproper_superset?(set) set.is_a?(Set) orraiseArgumentError, "value must be a set"returnfalseifsize<=set.sizeset.all? { |o|include?(o) } end
Equivalent to #delete_if, but returns nil if no changes were made.
# File set.rb, line 333defreject!(&block) blockorreturnenum_for(__method__) n = sizedelete_if(&block) size==n?nil:selfend
Replaces the contents of the set with the contents of the given enumerable object and returns self.
# File set.rb, line 142defreplace(enum) ifenum.instance_of?(self.class) @hash.replace(enum.instance_variable_get(:@hash)) elseclearmerge(enum) endselfend
Equivalent to #keep_if, but returns nil if no changes were made.
# File set.rb, line 342defselect!(&block) blockorreturnenum_for(__method__) n = sizekeep_if(&block) size==n?nil:selfend
Returns the number of elements.
# File set.rb, line 124defsize@hash.sizeend
Returns true if the set is a subset of the given set.
# File set.rb, line 226defsubset?(set) set.is_a?(Set) orraiseArgumentError, "value must be a set"returnfalseifset.size<sizeall? { |o|set.include?(o) } end
Deletes every element that appears in the given enumerable object and returns self.
# File set.rb, line 363defsubtract(enum) do_with_enum(enum) { |o|delete(o) } selfend
Returns true if the set is a superset of the given set.
# File set.rb, line 210defsuperset?(set) set.is_a?(Set) orraiseArgumentError, "value must be a set"returnfalseifsize<set.sizeset.all? { |o|include?(o) } end
Converts the set to an array. The order of elements is uncertain.
# File set.rb, line 154defto_a@hash.keysend
Returns self if no arguments are given. Otherwise, converts the set to another with klass.new(self, *args, &block).
In subclasses, returns klass.new(self, *args, &block) unless overridden.
# File set.rb, line 163defto_set(klass = Set, *args, &block) returnselfifinstance_of?(Set) &&klass==Set&&block.nil?&&args.empty?klass.new(self, *args, &block) end
