зеркало из https://github.com/github/ruby.git
861 строка
25 KiB
Ruby
861 строка
25 KiB
Ruby
# frozen_string_literal: true
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# :markup: markdown
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#
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# set.rb - defines the Set class
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#
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# Copyright (c) 2002-2020 Akinori MUSHA <knu@iDaemons.org>
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#
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# Documentation by Akinori MUSHA and Gavin Sinclair.
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#
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# All rights reserved. You can redistribute and/or modify it under the same
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# terms as Ruby.
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##
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# This library provides the Set class, which deals with a collection
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# of unordered values with no duplicates. It is a hybrid of Array's
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# intuitive inter-operation facilities and Hash's fast lookup.
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#
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# The method `to_set` is added to Enumerable for convenience.
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#
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# Set implements a collection of unordered values with no duplicates.
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# This is a hybrid of Array's intuitive inter-operation facilities and
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# Hash's fast lookup.
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#
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# Set is easy to use with Enumerable objects (implementing `each`).
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# Most of the initializer methods and binary operators accept generic
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# Enumerable objects besides sets and arrays. An Enumerable object
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# can be converted to Set using the `to_set` method.
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#
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# Set uses Hash as storage, so you must note the following points:
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#
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# * Equality of elements is determined according to Object#eql? and
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# Object#hash. Use Set#compare_by_identity to make a set compare
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# its elements by their identity.
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# * Set assumes that the identity of each element does not change
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# while it is stored. Modifying an element of a set will render the
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# set to an unreliable state.
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# * When a string is to be stored, a frozen copy of the string is
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# stored instead unless the original string is already frozen.
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#
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# ## Comparison
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#
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# The comparison operators `<`, `>`, `<=`, and `>=` are implemented as
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# shorthand for the {proper_,}{subset?,superset?} methods. The `<=>`
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# operator reflects this order, or return `nil` for sets that both
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# have distinct elements (`{x, y}` vs. `{x, z}` for example).
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#
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# ## Example
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#
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# ```ruby
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# require 'set'
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# s1 = Set[1, 2] #=> #<Set: {1, 2}>
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# s2 = [1, 2].to_set #=> #<Set: {1, 2}>
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# s1 == s2 #=> true
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# s1.add("foo") #=> #<Set: {1, 2, "foo"}>
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# s1.merge([2, 6]) #=> #<Set: {1, 2, "foo", 6}>
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# s1.subset?(s2) #=> false
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# s2.subset?(s1) #=> true
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# ```
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#
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# ## Contact
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#
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# - Akinori MUSHA <<knu@iDaemons.org>> (current maintainer)
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#
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# ## What's Here
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#
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# First, what's elsewhere. \Class \Set:
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#
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# - Inherits from {class Object}[https://docs.ruby-lang.org/en/master/Object.html#class-Object-label-What-27s+Here].
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# - Includes {module Enumerable}[https://docs.ruby-lang.org/en/master/Enumerable.html#module-Enumerable-label-What-27s+Here],
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# which provides dozens of additional methods.
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#
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# In particular, class \Set does not have many methods of its own
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# for fetching or for iterating.
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# Instead, it relies on those in \Enumerable.
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#
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# Here, class \Set provides methods that are useful for:
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#
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# - [Creating a Set](#class-Set-label-Methods+for+Creating+a+Set)
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# - [Set Operations](#class-Set-label-Methods+for+Set+Operations)
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# - [Comparing](#class-Set-label-Methods+for+Comparing)
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# - [Querying](#class-Set-label-Methods+for+Querying)
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# - [Assigning](#class-Set-label-Methods+for+Assigning)
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# - [Deleting](#class-Set-label-Methods+for+Deleting)
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# - [Converting](#class-Set-label-Methods+for+Converting)
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# - [Iterating](#class-Set-label-Methods+for+Iterating)
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# - [And more....](#class-Set-label-Other+Methods)
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#
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# ### Methods for Creating a \Set
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#
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# - ::[]:
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# Returns a new set containing the given objects.
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# - ::new:
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# Returns a new set containing either the given objects
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# (if no block given) or the return values from the called block
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# (if a block given).
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#
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# ### Methods for \Set Operations
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#
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# - [|](#method-i-7C) (aliased as #union and #+):
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# Returns a new set containing all elements from +self+
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# and all elements from a given enumerable (no duplicates).
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# - [&](#method-i-26) (aliased as #intersection):
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# Returns a new set containing all elements common to +self+
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# and a given enumerable.
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# - [-](#method-i-2D) (aliased as #difference):
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# Returns a copy of +self+ with all elements
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# in a given enumerable removed.
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# - [\^](#method-i-5E):
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# Returns a new set containing all elements from +self+
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# and a given enumerable except those common to both.
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#
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# ### Methods for Comparing
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#
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# - [<=>](#method-i-3C-3D-3E):
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# Returns -1, 0, or 1 as +self+ is less than, equal to,
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# or greater than a given object.
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# - [==](#method-i-3D-3D):
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# Returns whether +self+ and a given enumerable are equal,
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# as determined by Object#eql?.
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# - \#compare_by_identity?:
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# Returns whether the set considers only identity
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# when comparing elements.
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#
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# ### Methods for Querying
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#
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# - \#length (aliased as #size):
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# Returns the count of elements.
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# - \#empty?:
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# Returns whether the set has no elements.
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# - \#include? (aliased as #member? and #===):
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# Returns whether a given object is an element in the set.
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# - \#subset? (aliased as [<=](#method-i-3C-3D)):
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# Returns whether a given object is a subset of the set.
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# - \#proper_subset? (aliased as [<](#method-i-3C)):
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# Returns whether a given enumerable is a proper subset of the set.
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# - \#superset? (aliased as [>=](#method-i-3E-3D])):
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# Returns whether a given enumerable is a superset of the set.
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# - \#proper_superset? (aliased as [>](#method-i-3E)):
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# Returns whether a given enumerable is a proper superset of the set.
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# - \#disjoint?:
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# Returns +true+ if the set and a given enumerable
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# have no common elements, +false+ otherwise.
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# - \#intersect?:
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# Returns +true+ if the set and a given enumerable:
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# have any common elements, +false+ otherwise.
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# - \#compare_by_identity?:
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# Returns whether the set considers only identity
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# when comparing elements.
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#
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# ### Methods for Assigning
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#
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# - \#add (aliased as #<<):
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# Adds a given object to the set; returns +self+.
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# - \#add?:
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# If the given object is not an element in the set,
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# adds it and returns +self+; otherwise, returns +nil+.
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# - \#merge:
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# Adds each given object to the set; returns +self+.
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# - \#replace:
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# Replaces the contents of the set with the contents
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# of a given enumerable.
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#
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# ### Methods for Deleting
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#
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# - \#clear:
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# Removes all elements in the set; returns +self+.
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# - \#delete:
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# Removes a given object from the set; returns +self+.
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# - \#delete?:
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# If the given object is an element in the set,
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# removes it and returns +self+; otherwise, returns +nil+.
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# - \#subtract:
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# Removes each given object from the set; returns +self+.
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# - \#delete_if - Removes elements specified by a given block.
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# - \#select! (aliased as #filter!):
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# Removes elements not specified by a given block.
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# - \#keep_if:
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# Removes elements not specified by a given block.
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# - \#reject!
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# Removes elements specified by a given block.
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#
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# ### Methods for Converting
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#
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# - \#classify:
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# Returns a hash that classifies the elements,
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# as determined by the given block.
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# - \#collect! (aliased as #map!):
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# Replaces each element with a block return-value.
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# - \#divide:
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# Returns a hash that classifies the elements,
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# as determined by the given block;
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# differs from #classify in that the block may accept
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# either one or two arguments.
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# - \#flatten:
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# Returns a new set that is a recursive flattening of +self+.
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# \#flatten!:
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# Replaces each nested set in +self+ with the elements from that set.
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# - \#inspect (aliased as #to_s):
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# Returns a string displaying the elements.
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# - \#join:
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# Returns a string containing all elements, converted to strings
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# as needed, and joined by the given record separator.
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# - \#to_a:
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# Returns an array containing all set elements.
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# - \#to_set:
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# Returns +self+ if given no arguments and no block;
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# with a block given, returns a new set consisting of block
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# return values.
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#
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# ### Methods for Iterating
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#
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# - \#each:
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# Calls the block with each successive element; returns +self+.
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#
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# ### Other Methods
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#
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# - \#reset:
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# Resets the internal state; useful if an object
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# has been modified while an element in the set.
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#
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class Set
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include Enumerable
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# Creates a new set containing the given objects.
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#
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# Set[1, 2] # => #<Set: {1, 2}>
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# Set[1, 2, 1] # => #<Set: {1, 2}>
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# Set[1, 'c', :s] # => #<Set: {1, "c", :s}>
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def self.[](*ary)
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new(ary)
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end
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# Creates a new set containing the elements of the given enumerable
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# object.
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#
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# If a block is given, the elements of enum are preprocessed by the
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# given block.
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#
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# Set.new([1, 2]) #=> #<Set: {1, 2}>
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# Set.new([1, 2, 1]) #=> #<Set: {1, 2}>
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# Set.new([1, 'c', :s]) #=> #<Set: {1, "c", :s}>
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# Set.new(1..5) #=> #<Set: {1, 2, 3, 4, 5}>
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# Set.new([1, 2, 3]) { |x| x * x } #=> #<Set: {1, 4, 9}>
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def initialize(enum = nil, &block) # :yields: o
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@hash ||= Hash.new(false)
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enum.nil? and return
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if block
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do_with_enum(enum) { |o| add(block[o]) }
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else
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merge(enum)
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end
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end
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# Makes the set compare its elements by their identity and returns
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# self. This method may not be supported by all subclasses of Set.
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def compare_by_identity
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if @hash.respond_to?(:compare_by_identity)
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@hash.compare_by_identity
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self
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else
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raise NotImplementedError, "#{self.class.name}\##{__method__} is not implemented"
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end
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end
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# Returns true if the set will compare its elements by their
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# identity. Also see Set#compare_by_identity.
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def compare_by_identity?
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@hash.respond_to?(:compare_by_identity?) && @hash.compare_by_identity?
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end
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def do_with_enum(enum, &block) # :nodoc:
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if enum.respond_to?(:each_entry)
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enum.each_entry(&block) if block
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elsif enum.respond_to?(:each)
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enum.each(&block) if block
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else
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raise ArgumentError, "value must be enumerable"
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end
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end
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private :do_with_enum
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# Dup internal hash.
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def initialize_dup(orig)
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super
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@hash = orig.instance_variable_get(:@hash).dup
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end
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if Kernel.instance_method(:initialize_clone).arity != 1
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# Clone internal hash.
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def initialize_clone(orig, **options)
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super
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@hash = orig.instance_variable_get(:@hash).clone(**options)
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end
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else
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# Clone internal hash.
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def initialize_clone(orig)
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super
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@hash = orig.instance_variable_get(:@hash).clone
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end
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end
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def freeze # :nodoc:
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@hash.freeze
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super
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end
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# Returns the number of elements.
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def size
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@hash.size
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end
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alias length size
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# Returns true if the set contains no elements.
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def empty?
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@hash.empty?
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end
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# Removes all elements and returns self.
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#
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# set = Set[1, 'c', :s] #=> #<Set: {1, "c", :s}>
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# set.clear #=> #<Set: {}>
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# set #=> #<Set: {}>
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def clear
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@hash.clear
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self
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end
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# Replaces the contents of the set with the contents of the given
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# enumerable object and returns self.
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#
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# set = Set[1, 'c', :s] #=> #<Set: {1, "c", :s}>
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# set.replace([1, 2]) #=> #<Set: {1, 2}>
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# set #=> #<Set: {1, 2}>
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def replace(enum)
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if enum.instance_of?(self.class)
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@hash.replace(enum.instance_variable_get(:@hash))
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self
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else
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do_with_enum(enum) # make sure enum is enumerable before calling clear
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clear
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merge(enum)
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end
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end
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# Converts the set to an array. The order of elements is uncertain.
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#
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# Set[1, 2].to_a #=> [1, 2]
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# Set[1, 'c', :s].to_a #=> [1, "c", :s]
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def to_a
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@hash.keys
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end
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# Returns self if no arguments are given. Otherwise, converts the
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# set to another with `klass.new(self, *args, &block)`.
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#
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# In subclasses, returns `klass.new(self, *args, &block)` unless
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# overridden.
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def to_set(klass = Set, *args, &block)
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return self if instance_of?(Set) && klass == Set && block.nil? && args.empty?
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klass.new(self, *args, &block)
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end
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def flatten_merge(set, seen = Set.new) # :nodoc:
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set.each { |e|
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if e.is_a?(Set)
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if seen.include?(e_id = e.object_id)
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raise ArgumentError, "tried to flatten recursive Set"
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end
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seen.add(e_id)
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flatten_merge(e, seen)
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seen.delete(e_id)
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else
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add(e)
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end
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}
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self
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end
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protected :flatten_merge
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# Returns a new set that is a copy of the set, flattening each
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# containing set recursively.
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def flatten
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self.class.new.flatten_merge(self)
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end
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# Equivalent to Set#flatten, but replaces the receiver with the
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# result in place. Returns nil if no modifications were made.
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def flatten!
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replace(flatten()) if any? { |e| e.is_a?(Set) }
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end
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# Returns true if the set contains the given object.
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#
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# Note that <code>include?</code> and <code>member?</code> do not test member
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# equality using <code>==</code> as do other Enumerables.
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#
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# See also Enumerable#include?
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def include?(o)
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@hash[o]
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end
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alias member? include?
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# Returns true if the set is a superset of the given set.
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def superset?(set)
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case
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when set.instance_of?(self.class) && @hash.respond_to?(:>=)
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@hash >= set.instance_variable_get(:@hash)
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when set.is_a?(Set)
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size >= set.size && set.all? { |o| include?(o) }
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else
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raise ArgumentError, "value must be a set"
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end
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end
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alias >= superset?
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# Returns true if the set is a proper superset of the given set.
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def proper_superset?(set)
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case
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when set.instance_of?(self.class) && @hash.respond_to?(:>)
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@hash > set.instance_variable_get(:@hash)
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when set.is_a?(Set)
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size > set.size && set.all? { |o| include?(o) }
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else
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raise ArgumentError, "value must be a set"
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end
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end
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alias > proper_superset?
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# Returns true if the set is a subset of the given set.
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def subset?(set)
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case
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when set.instance_of?(self.class) && @hash.respond_to?(:<=)
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@hash <= set.instance_variable_get(:@hash)
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when set.is_a?(Set)
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size <= set.size && all? { |o| set.include?(o) }
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else
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raise ArgumentError, "value must be a set"
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end
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end
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alias <= subset?
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# Returns true if the set is a proper subset of the given set.
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def proper_subset?(set)
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case
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when set.instance_of?(self.class) && @hash.respond_to?(:<)
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@hash < set.instance_variable_get(:@hash)
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when set.is_a?(Set)
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size < set.size && all? { |o| set.include?(o) }
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else
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raise ArgumentError, "value must be a set"
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end
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end
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alias < proper_subset?
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# Returns 0 if the set are equal,
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# -1 / +1 if the set is a proper subset / superset of the given set,
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# or nil if they both have unique elements.
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def <=>(set)
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return unless set.is_a?(Set)
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case size <=> set.size
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when -1 then -1 if proper_subset?(set)
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when +1 then +1 if proper_superset?(set)
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else 0 if self.==(set)
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end
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end
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# Returns true if the set and the given enumerable have at least one
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# element in common.
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#
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# Set[1, 2, 3].intersect? Set[4, 5] #=> false
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# Set[1, 2, 3].intersect? Set[3, 4] #=> true
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# Set[1, 2, 3].intersect? 4..5 #=> false
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# Set[1, 2, 3].intersect? [3, 4] #=> true
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def intersect?(set)
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case set
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when Set
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if size < set.size
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any? { |o| set.include?(o) }
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else
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set.any? { |o| include?(o) }
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end
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when Enumerable
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set.any? { |o| include?(o) }
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else
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raise ArgumentError, "value must be enumerable"
|
|
end
|
|
end
|
|
|
|
# Returns true if the set and the given enumerable have
|
|
# no element in common. This method is the opposite of `intersect?`.
|
|
#
|
|
# Set[1, 2, 3].disjoint? Set[3, 4] #=> false
|
|
# Set[1, 2, 3].disjoint? Set[4, 5] #=> true
|
|
# Set[1, 2, 3].disjoint? [3, 4] #=> false
|
|
# Set[1, 2, 3].disjoint? 4..5 #=> true
|
|
def disjoint?(set)
|
|
!intersect?(set)
|
|
end
|
|
|
|
# Calls the given block once for each element in the set, passing
|
|
# the element as parameter. Returns an enumerator if no block is
|
|
# given.
|
|
def each(&block)
|
|
block or return enum_for(__method__) { size }
|
|
@hash.each_key(&block)
|
|
self
|
|
end
|
|
|
|
# Adds the given object to the set and returns self. Use `merge` to
|
|
# add many elements at once.
|
|
#
|
|
# Set[1, 2].add(3) #=> #<Set: {1, 2, 3}>
|
|
# Set[1, 2].add([3, 4]) #=> #<Set: {1, 2, [3, 4]}>
|
|
# Set[1, 2].add(2) #=> #<Set: {1, 2}>
|
|
def add(o)
|
|
@hash[o] = true
|
|
self
|
|
end
|
|
alias << add
|
|
|
|
# Adds the given object to the set and returns self. If the
|
|
# object is already in the set, returns nil.
|
|
#
|
|
# Set[1, 2].add?(3) #=> #<Set: {1, 2, 3}>
|
|
# Set[1, 2].add?([3, 4]) #=> #<Set: {1, 2, [3, 4]}>
|
|
# Set[1, 2].add?(2) #=> nil
|
|
def add?(o)
|
|
add(o) unless include?(o)
|
|
end
|
|
|
|
# Deletes the given object from the set and returns self. Use
|
|
# `subtract` to delete many items at once.
|
|
def delete(o)
|
|
@hash.delete(o)
|
|
self
|
|
end
|
|
|
|
# Deletes the given object from the set and returns self. If the
|
|
# object is not in the set, returns nil.
|
|
def delete?(o)
|
|
delete(o) if include?(o)
|
|
end
|
|
|
|
# Deletes every element of the set for which block evaluates to
|
|
# true, and returns self. Returns an enumerator if no block is
|
|
# given.
|
|
def delete_if
|
|
block_given? or return enum_for(__method__) { size }
|
|
# @hash.delete_if should be faster, but using it breaks the order
|
|
# of enumeration in subclasses.
|
|
select { |o| yield o }.each { |o| @hash.delete(o) }
|
|
self
|
|
end
|
|
|
|
# Deletes every element of the set for which block evaluates to
|
|
# false, and returns self. Returns an enumerator if no block is
|
|
# given.
|
|
def keep_if
|
|
block_given? or return enum_for(__method__) { size }
|
|
# @hash.keep_if should be faster, but using it breaks the order of
|
|
# enumeration in subclasses.
|
|
reject { |o| yield o }.each { |o| @hash.delete(o) }
|
|
self
|
|
end
|
|
|
|
# Replaces the elements with ones returned by `collect()`.
|
|
# Returns an enumerator if no block is given.
|
|
def collect!
|
|
block_given? or return enum_for(__method__) { size }
|
|
set = self.class.new
|
|
each { |o| set << yield(o) }
|
|
replace(set)
|
|
end
|
|
alias map! collect!
|
|
|
|
# Equivalent to Set#delete_if, but returns nil if no changes were
|
|
# made. Returns an enumerator if no block is given.
|
|
def reject!(&block)
|
|
block or return enum_for(__method__) { size }
|
|
n = size
|
|
delete_if(&block)
|
|
self if size != n
|
|
end
|
|
|
|
# Equivalent to Set#keep_if, but returns nil if no changes were
|
|
# made. Returns an enumerator if no block is given.
|
|
def select!(&block)
|
|
block or return enum_for(__method__) { size }
|
|
n = size
|
|
keep_if(&block)
|
|
self if size != n
|
|
end
|
|
|
|
# Equivalent to Set#select!
|
|
alias filter! select!
|
|
|
|
# Merges the elements of the given enumerable object to the set and
|
|
# returns self.
|
|
def merge(enum)
|
|
if enum.instance_of?(self.class)
|
|
@hash.update(enum.instance_variable_get(:@hash))
|
|
else
|
|
do_with_enum(enum) { |o| add(o) }
|
|
end
|
|
|
|
self
|
|
end
|
|
|
|
# Deletes every element that appears in the given enumerable object
|
|
# and returns self.
|
|
def subtract(enum)
|
|
do_with_enum(enum) { |o| delete(o) }
|
|
self
|
|
end
|
|
|
|
# Returns a new set built by merging the set and the elements of the
|
|
# given enumerable object.
|
|
#
|
|
# Set[1, 2, 3] | Set[2, 4, 5] #=> #<Set: {1, 2, 3, 4, 5}>
|
|
# Set[1, 5, 'z'] | (1..6) #=> #<Set: {1, 5, "z", 2, 3, 4, 6}>
|
|
def |(enum)
|
|
dup.merge(enum)
|
|
end
|
|
alias + |
|
|
alias union |
|
|
|
|
# Returns a new set built by duplicating the set, removing every
|
|
# element that appears in the given enumerable object.
|
|
#
|
|
# Set[1, 3, 5] - Set[1, 5] #=> #<Set: {3}>
|
|
# Set['a', 'b', 'z'] - ['a', 'c'] #=> #<Set: {"b", "z"}>
|
|
def -(enum)
|
|
dup.subtract(enum)
|
|
end
|
|
alias difference -
|
|
|
|
# Returns a new set containing elements common to the set and the
|
|
# given enumerable object.
|
|
#
|
|
# Set[1, 3, 5] & Set[3, 2, 1] #=> #<Set: {3, 1}>
|
|
# Set['a', 'b', 'z'] & ['a', 'b', 'c'] #=> #<Set: {"a", "b"}>
|
|
def &(enum)
|
|
n = self.class.new
|
|
if enum.is_a?(Set)
|
|
if enum.size > size
|
|
each { |o| n.add(o) if enum.include?(o) }
|
|
else
|
|
enum.each { |o| n.add(o) if include?(o) }
|
|
end
|
|
else
|
|
do_with_enum(enum) { |o| n.add(o) if include?(o) }
|
|
end
|
|
n
|
|
end
|
|
alias intersection &
|
|
|
|
# Returns a new set containing elements exclusive between the set
|
|
# and the given enumerable object. `(set ^ enum)` is equivalent to
|
|
# `((set | enum) - (set & enum))`.
|
|
#
|
|
# Set[1, 2] ^ Set[2, 3] #=> #<Set: {3, 1}>
|
|
# Set[1, 'b', 'c'] ^ ['b', 'd'] #=> #<Set: {"d", 1, "c"}>
|
|
def ^(enum)
|
|
n = Set.new(enum)
|
|
each { |o| n.add(o) unless n.delete?(o) }
|
|
n
|
|
end
|
|
|
|
# Returns true if two sets are equal. The equality of each couple
|
|
# of elements is defined according to Object#eql?.
|
|
#
|
|
# Set[1, 2] == Set[2, 1] #=> true
|
|
# Set[1, 3, 5] == Set[1, 5] #=> false
|
|
# Set['a', 'b', 'c'] == Set['a', 'c', 'b'] #=> true
|
|
# Set['a', 'b', 'c'] == ['a', 'c', 'b'] #=> false
|
|
def ==(other)
|
|
if self.equal?(other)
|
|
true
|
|
elsif other.instance_of?(self.class)
|
|
@hash == other.instance_variable_get(:@hash)
|
|
elsif other.is_a?(Set) && self.size == other.size
|
|
other.all? { |o| @hash.include?(o) }
|
|
else
|
|
false
|
|
end
|
|
end
|
|
|
|
def hash # :nodoc:
|
|
@hash.hash
|
|
end
|
|
|
|
def eql?(o) # :nodoc:
|
|
return false unless o.is_a?(Set)
|
|
@hash.eql?(o.instance_variable_get(:@hash))
|
|
end
|
|
|
|
# Resets the internal state after modification to existing elements
|
|
# and returns self.
|
|
#
|
|
# Elements will be reindexed and deduplicated.
|
|
def reset
|
|
if @hash.respond_to?(:rehash)
|
|
@hash.rehash # This should perform frozenness check.
|
|
else
|
|
raise FrozenError, "can't modify frozen #{self.class.name}" if frozen?
|
|
end
|
|
self
|
|
end
|
|
|
|
# Returns true if the given object is a member of the set,
|
|
# and false otherwise.
|
|
#
|
|
# Used in case statements:
|
|
#
|
|
# require 'set'
|
|
#
|
|
# case :apple
|
|
# when Set[:potato, :carrot]
|
|
# "vegetable"
|
|
# when Set[:apple, :banana]
|
|
# "fruit"
|
|
# end
|
|
# # => "fruit"
|
|
#
|
|
# Or by itself:
|
|
#
|
|
# Set[1, 2, 3] === 2 #=> true
|
|
# Set[1, 2, 3] === 4 #=> false
|
|
#
|
|
alias === include?
|
|
|
|
# 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.
|
|
#
|
|
# require 'set'
|
|
# files = Set.new(Dir.glob("*.rb"))
|
|
# hash = files.classify { |f| File.mtime(f).year }
|
|
# hash #=> {2000=>#<Set: {"a.rb", "b.rb"}>,
|
|
# # 2001=>#<Set: {"c.rb", "d.rb", "e.rb"}>,
|
|
# # 2002=>#<Set: {"f.rb"}>}
|
|
#
|
|
# Returns an enumerator if no block is given.
|
|
def classify # :yields: o
|
|
block_given? or return enum_for(__method__) { size }
|
|
|
|
h = {}
|
|
|
|
each { |i|
|
|
(h[yield(i)] ||= self.class.new).add(i)
|
|
}
|
|
|
|
h
|
|
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).
|
|
#
|
|
# require 'set'
|
|
# numbers = Set[1, 3, 4, 6, 9, 10, 11]
|
|
# set = numbers.divide { |i,j| (i - j).abs == 1 }
|
|
# set #=> #<Set: {#<Set: {1}>,
|
|
# # #<Set: {11, 9, 10}>,
|
|
# # #<Set: {3, 4}>,
|
|
# # #<Set: {6}>}>
|
|
#
|
|
# Returns an enumerator if no block is given.
|
|
def divide(&func)
|
|
func or return enum_for(__method__) { size }
|
|
|
|
if func.arity == 2
|
|
require 'tsort'
|
|
|
|
class << dig = {} # :nodoc:
|
|
include TSort
|
|
|
|
alias tsort_each_node each_key
|
|
def tsort_each_child(node, &block)
|
|
fetch(node).each(&block)
|
|
end
|
|
end
|
|
|
|
each { |u|
|
|
dig[u] = a = []
|
|
each{ |v| func.call(u, v) and a << v }
|
|
}
|
|
|
|
set = Set.new()
|
|
dig.each_strongly_connected_component { |css|
|
|
set.add(self.class.new(css))
|
|
}
|
|
set
|
|
else
|
|
Set.new(classify(&func).values)
|
|
end
|
|
end
|
|
|
|
# Returns a string created by converting each element of the set to a string
|
|
# See also: Array#join
|
|
def join(separator=nil)
|
|
to_a.join(separator)
|
|
end
|
|
|
|
InspectKey = :__inspect_key__ # :nodoc:
|
|
|
|
# Returns a string containing a human-readable representation of the
|
|
# set ("#<Set: {element1, element2, ...}>").
|
|
def inspect
|
|
ids = (Thread.current[InspectKey] ||= [])
|
|
|
|
if ids.include?(object_id)
|
|
return sprintf('#<%s: {...}>', self.class.name)
|
|
end
|
|
|
|
ids << object_id
|
|
begin
|
|
return sprintf('#<%s: {%s}>', self.class, to_a.inspect[1..-2])
|
|
ensure
|
|
ids.pop
|
|
end
|
|
end
|
|
|
|
alias to_s inspect
|
|
|
|
def pretty_print(pp) # :nodoc:
|
|
pp.group(1, sprintf('#<%s:', self.class.name), '>') {
|
|
pp.breakable
|
|
pp.group(1, '{', '}') {
|
|
pp.seplist(self) { |o|
|
|
pp.pp o
|
|
}
|
|
}
|
|
}
|
|
end
|
|
|
|
def pretty_print_cycle(pp) # :nodoc:
|
|
pp.text sprintf('#<%s: {%s}>', self.class.name, empty? ? '' : '...')
|
|
end
|
|
end
|
|
|
|
module Enumerable
|
|
# Makes a set from the enumerable object with given arguments.
|
|
# Needs to `require "set"` to use this method.
|
|
def to_set(klass = Set, *args, &block)
|
|
klass.new(self, *args, &block)
|
|
end unless method_defined?(:to_set)
|
|
end
|
|
|
|
autoload :SortedSet, "#{__dir__}/set/sorted_set"
|