Results for: "to_proc"

Returns true for IPv6 multicast site-local scope address. It returns false otherwise.

Returns true for IPv6 multicast organization-local scope address. It returns false otherwise.

Breaks the buffer into lines that are shorter than maxwidth

The block passed to this method will be called just before running the RDoc generator. It is allowed to modify RDoc::Task attributes inside the block.

Task description for the rdoc task or its renamed equivalent

Task description for the rerdoc task or its renamed description

Returns the value of the local variable symbol.

def foo
  a = 1
  binding.local_variable_get(:a) #=> 1
  binding.local_variable_get(:b) #=> NameError
end

This method is the short version of the following code:

binding.eval("#{symbol}")

Set local variable named symbol as obj.

def foo
  a = 1
  bind = binding
  bind.local_variable_set(:a, 2) # set existing local variable `a'
  bind.local_variable_set(:b, 3) # create new local variable `b'
                                 # `b' exists only in binding

  p bind.local_variable_get(:a)  #=> 2
  p bind.local_variable_get(:b)  #=> 3
  p a                            #=> 2
  p b                            #=> NameError
end

This method behaves similarly to the following code:

binding.eval("#{symbol} = #{obj}")

if obj can be dumped in Ruby code.

Returns true if a local variable symbol exists.

def foo
  a = 1
  binding.local_variable_defined?(:a) #=> true
  binding.local_variable_defined?(:b) #=> false
end

This method is the short version of the following code:

binding.eval("defined?(#{symbol}) == 'local-variable'")

Returns the last win32 Error of the current executing Thread or nil if none

Sets the last win32 Error of the current executing Thread to error

Starts tracing object allocations from the ObjectSpace extension module.

For example:

require 'objspace'

class C
  include ObjectSpace

  def foo
    trace_object_allocations do
      obj = Object.new
      p "#{allocation_sourcefile(obj)}:#{allocation_sourceline(obj)}"
    end
  end
end

C.new.foo #=> "objtrace.rb:8"

This example has included the ObjectSpace module to make it easier to read, but you can also use the ::trace_object_allocations notation (recommended).

Note that this feature introduces a huge performance decrease and huge memory consumption.

Returns the class for the given object.

class A
  def foo
    ObjectSpace::trace_object_allocations do
      obj = Object.new
      p "#{ObjectSpace::allocation_class_path(obj)}"
    end
  end
end

A.new.foo #=> "Class"

See ::trace_object_allocations for more information and examples.

Returns the method identifier for the given object.

class A
  include ObjectSpace

  def foo
    trace_object_allocations do
      obj = Object.new
      p "#{allocation_class_path(obj)}##{allocation_method_id(obj)}"
    end
  end
end

A.new.foo #=> "Class#new"

See ::trace_object_allocations for more information and examples.

MRI specific feature

Return all reachable objects from ‘obj’.

This method returns all reachable objects from ‘obj’.

If ‘obj’ has two or more references to the same object ‘x’, then returned array only includes one ‘x’ object.

If ‘obj’ is a non-markable (non-heap management) object such as true, false, nil, symbols and Fixnums (and Flonum) then it simply returns nil.

If ‘obj’ has references to an internal object, then it returns instances of ObjectSpace::InternalObjectWrapper class. This object contains a reference to an internal object and you can check the type of internal object with ‘type’ method.

If ‘obj’ is instance of ObjectSpace::InternalObjectWrapper class, then this method returns all reachable object from an internal object, which is pointed by ‘obj’.

With this method, you can find memory leaks.

This method is only expected to work except with C Ruby.

Example:

ObjectSpace.reachable_objects_from(['a', 'b', 'c'])
#=> [Array, 'a', 'b', 'c']

ObjectSpace.reachable_objects_from(['a', 'a', 'a'])
#=> [Array, 'a', 'a', 'a'] # all 'a' strings have different object id

ObjectSpace.reachable_objects_from([v = 'a', v, v])
#=> [Array, 'a']

ObjectSpace.reachable_objects_from(1)
#=> nil # 1 is not markable (heap managed) object

Specifies a Proc object proc to call after the first prompt has been printed and just before readline starts reading input characters.

See GNU Readline’s rl_pre_input_hook variable.

Raises ArgumentError if proc does not respond to the call method.

Raises NotImplementedError if the using readline library does not support.

Returns a Proc object proc to call after the first prompt has been printed and just before readline starts reading input characters. The default is nil.

Raises NotImplementedError if the using readline library does not support.

See Mutex#try_lock

The file name and line number of the caller of the caller of this method.

locking methods.

locking methods.

Returns strongly connected components as an array of arrays of nodes. The array is sorted from children to parents. Each elements of the array represents a strongly connected component.

class G
  include TSort
  def initialize(g)
    @g = g
  end
  def tsort_each_child(n, &b) @g[n].each(&b) end
  def tsort_each_node(&b) @g.each_key(&b) end
end

graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
p graph.strongly_connected_components #=> [[4], [2], [3], [1]]

graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
p graph.strongly_connected_components #=> [[4], [2, 3], [1]]