Returns true if the set is a subset of the given set.
Equivalent to Set#keep_if, but returns nil if no changes were made. Returns an enumerator if no block is given.
Equivalent to Set#select!
Merges the elements of the given enumerable objects to the set and returns self.
Resets the internal state after modification to existing elements and returns self.
Elements will be reindexed and deduplicated.
With a block given, returns an array of values from self for which the block returns a truthy value:
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) a = joe.select {|value| value.is_a?(String) } a # => ["Joe Smith", "123 Maple, Anytown NC"] a = joe.select {|value| value.is_a?(Integer) } a # => [12345]
With no block given, returns an Enumerator.
With a block given, returns an array of values from self for which the block returns a truthy value:
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) a = joe.select {|value| value.is_a?(String) } a # => ["Joe Smith", "123 Maple, Anytown NC"] a = joe.select {|value| value.is_a?(Integer) } a # => [12345]
With no block given, returns an Enumerator.
Returns the values in self as an array:
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.to_a # => ["Joe Smith", "123 Maple, Anytown NC", 12345]
Related: members.
Like Symbol#<=>, but case-insensitive; equivalent to self.to_s.casecmp(object.to_s):
lower = :abc upper = :ABC upper.casecmp(lower) # => 0 lower.casecmp(lower) # => 0 lower.casecmp(upper) # => 0
Returns nil if self and object have incompatible encodings, or if object is not a symbol:
sym = 'äöü'.encode("ISO-8859-1").to_sym other_sym = 'ÄÖÜ' sym.casecmp(other_sym) # => nil :foo.casecmp(2) # => nil
Unlike Symbol#casecmp?, case-insensitivity does not work for characters outside of ‘A’..‘Z’ and ‘a’..‘z’:
lower = :äöü upper = :ÄÖÜ upper.casecmp(lower) # => -1 lower.casecmp(lower) # => 0 lower.casecmp(upper) # => 1
Related: Symbol#casecmp?, String#casecmp.
Returns true if self and object are equal after Unicode case folding, otherwise false:
lower = :abc upper = :ABC upper.casecmp?(lower) # => true lower.casecmp?(lower) # => true lower.casecmp?(upper) # => true
Returns nil if self and object have incompatible encodings, or if object is not a symbol:
sym = 'äöü'.encode("ISO-8859-1").to_sym other_sym = 'ÄÖÜ' sym.casecmp?(other_sym) # => nil :foo.casecmp?(2) # => nil
Unlike Symbol#casecmp, works for characters outside of ‘A’..‘Z’ and ‘a’..‘z’:
lower = :äöü upper = :ÄÖÜ upper.casecmp?(lower) # => true lower.casecmp?(lower) # => true lower.casecmp?(upper) # => true
Related: Symbol#casecmp, String#casecmp?.
Returns true if self is :'', false otherwise.
Callback invoked whenever a subclass of the current class is created.
Example:
class Foo def self.inherited(subclass) puts "New subclass: #{subclass}" end end class Bar < Foo end class Baz < Bar end
produces:
New subclass: Bar New subclass: Baz
Returns the superclass of class, or nil.
File.superclass #=> IO IO.superclass #=> Object Object.superclass #=> BasicObject class Foo; end class Bar < Foo; end Bar.superclass #=> Foo
Returns nil when the given class does not have a parent class:
BasicObject.superclass #=> nil
Returns an array of classes where the receiver is the direct superclass of the class, excluding singleton classes. The order of the returned array is not defined.
class A; end class B < A; end class C < B; end class D < A; end A.subclasses #=> [D, B] B.subclasses #=> [C] C.subclasses #=> []
Anonymous subclasses (not associated with a constant) are returned, too:
c = Class.new(A) A.subclasses # => [#<Class:0x00007f003c77bd78>, D, B]
Note that the parent does not hold references to subclasses and doesn’t prevent them from being garbage collected. This means that the subclass might disappear when all references to it are dropped:
# drop the reference to subclass, it can be garbage-collected now c = nil A.subclasses # It can be # => [#<Class:0x00007f003c77bd78>, D, B] # ...or just # => [D, B] # ...depending on whether garbage collector was run
Enters exclusive section.
Enters exclusive section and executes the block. Leaves the exclusive section automatically when the block exits. See example under MonitorMixin.
The opposite of Pathname#absolute?
It returns false if the pathname begins with a slash.
p = Pathname.new('/im/sure') p.relative? #=> false p = Pathname.new('not/so/sure') p.relative? #=> true
Creates a full path, including any intermediate directories that don’t yet exist.
See FileUtils.mkpath and FileUtils.mkdir_p
Returns the real (absolute) pathname for self in the actual filesystem.
Does not contain symlinks or useless dots, .. and ..
All components of the pathname must exist when this method is called.
Returns the real (absolute) pathname of self in the actual filesystem.
Does not contain symlinks or useless dots, .. and ..
The last component of the real pathname can be nonexistent.