Returns the path associated with the IO, or nil if there is no path associated with the IO. It is not guaranteed that the path exists on the filesystem.
$stdin.path # => "<STDIN>" File.open("testfile") {|f| f.path} # => "testfile"
Returns true if the underlying file descriptor of ios will be closed at its finalization or at calling close, otherwise false.
Sets auto-close flag.
f = File.open(File::NULL) IO.for_fd(f.fileno).close f.gets # raises Errno::EBADF f = File.open(File::NULL) g = IO.for_fd(f.fileno) g.autoclose = false g.close f.gets # won't cause Errno::EBADF
With no argument, returns the first element of self, if it exists:
(1..4).first # => 1 ('a'..'d').first # => "a"
With non-negative integer argument n given, returns the first n elements in an array:
(1..10).first(3) # => [1, 2, 3] (1..10).first(0) # => [] (1..4).first(50) # => [1, 2, 3, 4]
Raises an exception if there is no first element:
(..4).first # Raises RangeError
Returns true if object is an element of self, false otherwise:
(1..4).include?(2) # => true (1..4).include?(5) # => false (1..4).include?(4) # => true (1...4).include?(4) # => false ('a'..'d').include?('b') # => true ('a'..'d').include?('e') # => false ('a'..'d').include?('B') # => false ('a'..'d').include?('d') # => true ('a'...'d').include?('d') # => false
If begin and end are numeric, include? behaves like cover?
(1..3).include?(1.5) # => true (1..3).cover?(1.5) # => true
But when not numeric, the two methods may differ:
('a'..'d').include?('cc') # => false ('a'..'d').cover?('cc') # => true
Related: Range#cover?.
Returns true if the given argument is within self, false otherwise.
With non-range argument object, evaluates with <= and <.
For range self with included end value (exclude_end? == false), evaluates thus:
self.begin <= object <= self.end
Examples:
r = (1..4) r.cover?(1) # => true r.cover?(4) # => true r.cover?(0) # => false r.cover?(5) # => false r.cover?('foo') # => false r = ('a'..'d') r.cover?('a') # => true r.cover?('d') # => true r.cover?(' ') # => false r.cover?('e') # => false r.cover?(0) # => false
For range r with excluded end value (exclude_end? == true), evaluates thus:
r.begin <= object < r.end
Examples:
r = (1...4) r.cover?(1) # => true r.cover?(3) # => true r.cover?(0) # => false r.cover?(4) # => false r.cover?('foo') # => false r = ('a'...'d') r.cover?('a') # => true r.cover?('c') # => true r.cover?(' ') # => false r.cover?('d') # => false r.cover?(0) # => false
With range argument range, compares the first and last elements of self and range:
r = (1..4) r.cover?(1..4) # => true r.cover?(0..4) # => false r.cover?(1..5) # => false r.cover?('a'..'d') # => false r = (1...4) r.cover?(1..3) # => true r.cover?(1..4) # => false
If begin and end are numeric, cover? behaves like include?
(1..3).cover?(1.5) # => true (1..3).include?(1.5) # => true
But when not numeric, the two methods may differ:
('a'..'d').cover?('cc') # => true ('a'..'d').include?('cc') # => false
Returns false if either:
The begin value of self is larger than its end value.
An internal call to <=> returns nil; that is, the operands are not comparable.
Beginless ranges cover all values of the same type before the end, excluding the end for exclusive ranges. Beginless ranges cover ranges that end before the end of the beginless range, or at the end of the beginless range for inclusive ranges.
(..2).cover?(1) # => true (..2).cover?(2) # => true (..2).cover?(3) # => false (...2).cover?(2) # => false (..2).cover?("2") # => false (..2).cover?(..2) # => true (..2).cover?(...2) # => true (..2).cover?(.."2") # => false (...2).cover?(..2) # => false
Endless ranges cover all values of the same type after the beginning. Endless exclusive ranges do not cover endless inclusive ranges.
(2..).cover?(1) # => false (2..).cover?(3) # => true (2...).cover?(3) # => true (2..).cover?(2) # => true (2..).cover?("2") # => false (2..).cover?(2..) # => true (2..).cover?(2...) # => true (2..).cover?("2"..) # => false (2...).cover?(2..) # => false (2...).cover?(3...) # => true (2...).cover?(3..) # => false (3..).cover?(2..) # => false
Ranges that are both beginless and endless cover all values and ranges, and return true for all arguments, with the exception that beginless and endless exclusive ranges do not cover endless inclusive ranges.
(nil...).cover?(Object.new) # => true (nil...).cover?(nil...) # => true (nil..).cover?(nil...) # => true (nil...).cover?(nil..) # => false (nil...).cover?(1..) # => false
Related: Range#include?.
Returns true if range overlaps with self, false otherwise:
(0..2).overlap?(1..3) #=> true (0..2).overlap?(3..4) #=> false (0..).overlap?(..0) #=> true
With non-range argument, raises TypeError.
(1..3).overlap?(1) # TypeError
Returns false if an internal call to <=> returns nil; that is, the operands are not comparable.
(1..3).overlap?('a'..'d') # => false
Returns false if self or range is empty. “Empty range” means that its begin value is larger than, or equal for an exclusive range, its end value.
(4..1).overlap?(2..3) # => false (4..1).overlap?(..3) # => false (4..1).overlap?(2..) # => false (2...2).overlap?(1..2) # => false (1..4).overlap?(3..2) # => false (..4).overlap?(3..2) # => false (1..).overlap?(3..2) # => false (1..2).overlap?(2...2) # => false
Returns false if the begin value one of self and range is larger than, or equal if the other is an exclusive range, the end value of the other:
(4..5).overlap?(2..3) # => false (4..5).overlap?(2...4) # => false (1..2).overlap?(3..4) # => false (1...3).overlap?(3..4) # => false
Returns false if the end value one of self and range is larger than, or equal for an exclusive range, the end value of the other:
(4..5).overlap?(2..3) # => false (4..5).overlap?(2...4) # => false (1..2).overlap?(3..4) # => false (1...3).overlap?(3..4) # => false
Note that the method wouldn’t make any assumptions about the beginless range being actually empty, even if its upper bound is the minimum possible value of its type, so all this would return true:
(...-Float::INFINITY).overlap?(...-Float::INFINITY) # => true (..."").overlap?(..."") # => true (...[]).overlap?(...[]) # => true
Even if those ranges are effectively empty (no number can be smaller than -Float::INFINITY), they are still considered overlapping with themselves.
Related: Range#cover?.
Returns the numerator.
Rational(7).numerator #=> 7 Rational(7, 1).numerator #=> 7 Rational(9, -4).numerator #=> -9 Rational(-2, -10).numerator #=> 1
Returns true if rat is greater than 0.
Returns true if rat is less than 0.
Returns true if the case-insensitivity flag in self is set, false otherwise:
/a/.casefold? # => false /a/i.casefold? # => true /(?i:a)/.casefold? # => false
It returns the timeout interval for Regexp matching in second. nil means no default timeout configuration.
This configuration is per-object. The global configuration set by Regexp.timeout= is ignored if per-object configuration is set.
re = Regexp.new("^a*b?a*$", timeout: 1) re.timeout #=> 1.0 re =~ "a" * 100000 + "x" #=> regexp match timeout (RuntimeError)
It returns the current default timeout interval for Regexp matching in second. nil means no default timeout configuration.
It sets the default timeout interval for Regexp matching in second. nil means no default timeout configuration. This configuration is process-global. If you want to set timeout for each Regexp, use timeout keyword for Regexp.new.
Regexp.timeout = 1 /^a*b?a*$/ =~ "a" * 100000 + "x" #=> regexp match timeout (RuntimeError)
Removes all elements and returns self.
set = Set[1, 'c', :s] #=> #<Set: {1, "c", :s}> set.clear #=> #<Set: {}> set #=> #<Set: {}>
Returns true if the set contains no elements.
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.
Equivalent to Set#keep_if, but returns nil if no changes were made. Returns an enumerator if no block is given.
Returns true if the set is a subset of the given set.
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"}>
Returns true if the set contains the given object:
Set[1, 2, 3].include? 2 #=> true Set[1, 2, 3].include? 4 #=> false
Note that include? and member? do not test member equality using == as do other Enumerables.
This is aliased to ===, so it is usable in case expressions:
case :apple when Set[:potato, :carrot] "vegetable" when Set[:apple, :banana] "fruit" end # => "fruit"
See also Enumerable#include?
Equivalent to Set#keep_if, but returns nil if no changes were made. Returns an enumerator if no block is given.
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.