Comes from ripper, called on every parse error, msg is a string
Create a new AlternationPatternNode
node.
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.
Inspect a OptionalKeywordParameterNode
node.
Copy a OptionalKeywordParameterNode
node
When a block given, iterates backwards over the elements of self
, passing, in reverse order, each element to the block; returns self
:
a = [] [0, 1, 2].reverse_each {|element| a.push(element) } a # => [2, 1, 0]
Allows the array to be modified during iteration:
a = ['a', 'b', 'c'] a.reverse_each {|element| a.clear if element.start_with?('b') } a # => []
When no block given, returns a new Enumerator
.
Related: see Methods for Iterating.
With a block given, calls the block with each repeated combination of length size
of the elements of self
; each combination is an array; returns self
. The order of the combinations is indeterminate.
If a positive integer argument size
is given, calls the block with each size
-tuple repeated combination of the elements of self
. The number of combinations is (size+1)(size+2)/2
.
Examples:
size
is 1:
c = [] [0, 1, 2].repeated_combination(1) {|combination| c.push(combination) } c # => [[0], [1], [2]]
size
is 2:
c = [] [0, 1, 2].repeated_combination(2) {|combination| c.push(combination) } c # => [[0, 0], [0, 1], [0, 2], [1, 1], [1, 2], [2, 2]]
If size
is zero, calls the block once with an empty array.
If size
is negative, does not call the block:
[0, 1, 2].repeated_combination(-1) {|combination| fail 'Cannot happen' }
With no block given, returns a new Enumerator
.
Related: see Methods for Combining.
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 the backtrace (the list of code locations that led to the exception), as an array of Thread::Backtrace::Location
instances.
Example (assuming the code is stored in the file named t.rb
):
def division(numerator, denominator) numerator / denominator end begin division(1, 0) rescue => ex p ex.backtrace_locations # ["t.rb:2:in 'Integer#/'", "t.rb:2:in 'Object#division'", "t.rb:6:in '<main>'"] loc = ex.backtrace_locations.first p loc.class # Thread::Backtrace::Location p loc.path # "t.rb" p loc.lineno # 2 p loc.label # "Integer#/" end
The value returned by this method might be adjusted when raising (see Kernel#raise
), or during intermediate handling by set_backtrace
.
See also backtrace
that provide the same value as an array of strings. (Note though that two values might not be consistent with each other when backtraces are manually adjusted.)
See Backtraces.
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.
Returns the Ruby source filename and line number of the binding object.
Raises PStore::Error
if the calling code is not in a PStore#transaction
.
Returns the Ruby source filename and line number containing this proc or nil
if this proc was not defined in Ruby (i.e. native).
Returns the Ruby source filename and line number containing this method or nil if this method was not defined in Ruby (i.e. native).
Returns the Ruby source filename and line number containing this method or nil if this method was not defined in Ruby (i.e. native).
Returns the execution stack for the target thread—an array containing backtrace location objects.
See Thread::Backtrace::Location
for more information.
This method behaves similarly to Kernel#caller_locations
except it applies to a specific thread.
With a block given, calls the block with each element, but in reverse order; returns self
:
a = [] (1..4).reverse_each {|element| a.push(-element) } # => 1..4 a # => [-4, -3, -2, -1] a = [] %w[a b c d].reverse_each {|element| a.push(element) } # => ["a", "b", "c", "d"] a # => ["d", "c", "b", "a"] a = [] h.reverse_each {|element| a.push(element) } # => {:foo=>0, :bar=>1, :baz=>2} a # => [[:baz, 2], [:bar, 1], [:foo, 0]]
With no block given, returns an Enumerator
.
Returns the source file origin from the given object
.
See ::trace_object_allocations
for more information and examples.