Parse uri
into a [uri, option] pair.
The DRbProtocol
module asks each registered protocol in turn to try to parse the URI
. Each protocol signals that it does not handle that URI
by raising a DRbBadScheme
error. If no protocol recognises the URI
, then a DRbBadURI
error is raised.
Parse uri
into a [uri, option] pair.
The DRbProtocol
module asks each registered protocol in turn to try to parse the URI
. Each protocol signals that it does not handle that URI
by raising a DRbBadScheme
error. If no protocol recognises the URI
, then a DRbBadURI
error is raised.
Notifies observers of a change in state. See also Observable#notify_observers
Returns whether the HTTP
session is to be closed.
Terminates the RubyGems process with the given exit_code
Enumerates the parents of directory
.
Comes from ripper, called on every parse error, msg is a string
Get a single optional argument from the command line. If more than one argument is given, return only the first. Return nil if none are given.
Dispatch enter and leave events for OptionalKeywordParameterNode
nodes and continue walking the tree.
Copy a OptionalKeywordParameterNode
node
Iterates backwards over array elements.
When a block given, passes, in reverse order, each element to the block; returns self
:
a = [:foo, 'bar', 2] a.reverse_each {|element| puts "#{element.class} #{element}" }
Output:
Integer 2 String bar Symbol foo
Allows the array to be modified during iteration:
a = [:foo, 'bar', 2] a.reverse_each {|element| puts element; a.clear if element.to_s.start_with?('b') }
Output:
2 bar
When no block given, returns a new Enumerator:
a = [:foo, 'bar', 2] e = a.reverse_each e # => #<Enumerator: [:foo, "bar", 2]:reverse_each> a1 = e.each {|element| puts "#{element.class} #{element}" }
Output:
Integer 2 String bar Symbol foo
Related: each
, each_index
.
Calls the block with each repeated combination of length n
of the elements of self
; each combination is an Array; returns self
. The order of the combinations is indeterminate.
When a block and a positive Integer
argument n
are given, calls the block with each n
-tuple repeated combination of the elements of self
. The number of combinations is (n+1)(n+2)/2
.
n
= 1:
a = [0, 1, 2] a.repeated_combination(1) {|combination| p combination }
Output:
[0] [1] [2]
n
= 2:
a.repeated_combination(2) {|combination| p combination }
Output:
[0, 0] [0, 1] [0, 2] [1, 1] [1, 2] [2, 2]
If n
is zero, calls the block once with an empty Array.
If n
is negative, does not call the block:
a.repeated_combination(-1) {|combination| fail 'Cannot happen' }
Returns a new Enumerator
if no block given:
a = [0, 1, 2] a.repeated_combination(2) # => #<Enumerator: [0, 1, 2]:combination(2)>
Using Enumerators, it’s convenient to show the combinations and counts for some values of n
:
e = a.repeated_combination(0) e.size # => 1 e.to_a # => [[]] e = a.repeated_combination(1) e.size # => 3 e.to_a # => [[0], [1], [2]] e = a.repeated_combination(2) e.size # => 6 e.to_a # => [[0, 0], [0, 1], [0, 2], [1, 1], [1, 2], [2, 2]]
Like backtrace
, but returns each line of the execution stack as a Thread::Backtrace::Location
. Accepts the same arguments as backtrace
.
f = Fiber.new { Fiber.yield } f.resume loc = f.backtrace_locations.first loc.label #=> "yield" loc.path #=> "test.rb" loc.lineno #=> 1
Returns any backtrace associated with the exception. This method is similar to Exception#backtrace
, but the backtrace is an array of Thread::Backtrace::Location
.
This method is not affected by Exception#set_backtrace()
.
Creates module functions for the named methods. These functions may be called with the module as a receiver, and also become available as instance methods to classes that mix in the module. Module
functions are copies of the original, and so may be changed independently. The instance-method versions are made private. If used with no arguments, subsequently defined methods become module functions. String
arguments are converted to symbols. If a single argument is passed, it is returned. If no argument is passed, nil is returned. If multiple arguments are passed, the arguments are returned as an array.
module Mod def one "This is one" end module_function :one end class Cls include Mod def call_one one end end Mod.one #=> "This is one" c = Cls.new c.call_one #=> "This is one" module Mod def one "This is the new one" end end Mod.one #=> "This is one" c.call_one #=> "This is the new one"
Returns the fractional part of the day in range (Rational(0, 1)…Rational(1, 1)):
DateTime.new(2001,2,3,12).day_fraction # => (1/2)
With a block given, passes each element of self
to the block in reverse order:
a = [] (1..4).reverse_each {|element| a.push(element) } # => 1..4 a # => [4, 3, 2, 1] a = [] (1...4).reverse_each {|element| a.push(element) } # => 1...4 a # => [3, 2, 1]
With no block given, returns an enumerator.
Returns true if the set is a proper subset of the given set.
The block need not return a String object:
csv = CSV.open(path, headers: true) csv.header_convert {|header, field_info| header.to_sym } table = csv.read table.headers # => [:Name, :Value]
If converter_name
is given, the block is not called:
csv = CSV.open(path, headers: true) csv.header_convert(:downcase) {|header, field_info| fail 'Cannot happen' } table = csv.read table.headers # => ["name", "value"]
Raises a parse-time exception if converter_name
is not the name of a built-in field converter:
csv = CSV.open(path, headers: true) csv.header_convert(:nosuch) # Raises NoMethodError (undefined method `arity' for nil:NilClass) csv.read