Results for: "module_function"

Returns the status of the thread-local “abort on exception” condition for this thr.

The default is false.

See also abort_on_exception=.

There is also a class level method to set this for all threads, see ::abort_on_exception.

When set to true, if this thr is aborted by an exception, the raised exception will be re-raised in the main thread.

See also abort_on_exception.

There is also a class level method to set this for all threads, see ::abort_on_exception=.

Returns the status of the thread-local “report on exception” condition for this thr.

The default value when creating a Thread is the value of the global flag Thread.report_on_exception.

See also report_on_exception=.

There is also a class level method to set this for all new threads, see ::report_on_exception=.

When set to true, a message is printed on $stderr if an exception kills this thr. See ::report_on_exception for details.

See also report_on_exception.

There is also a class level method to set this for all new threads, see ::report_on_exception=.

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 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]]

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.

The graph is represented by each_node and each_child. each_node should have call method which yields for each node in the graph. each_child should have call method which takes a node argument and yields for each child node.

g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
each_node = lambda {|&b| g.each_key(&b) }
each_child = lambda {|n, &b| g[n].each(&b) }
p TSort.strongly_connected_components(each_node, each_child)
#=> [[4], [2], [3], [1]]

g = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
each_node = lambda {|&b| g.each_key(&b) }
each_child = lambda {|n, &b| g[n].each(&b) }
p TSort.strongly_connected_components(each_node, each_child)
#=> [[4], [2, 3], [1]]

Get the names of all sections in the current configuration.

Creates or an HTTP connection based on uri, or retrieves an existing connection, using a proxy if needed.

Returns whether the HTTP session is to be closed.

With a block given, calls the block with each repeated permutation of length size of the elements of self; each permutation is an array; returns self. The order of the permutations is indeterminate.

If a positive integer argument size is given, calls the block with each size-tuple repeated permutation of the elements of self. The number of permutations is self.size**size.

Examples:

• size is 1:

  p = []
  [0, 1, 2].repeated_permutation(1) {|permutation| p.push(permutation) }
  p # => [[0], [1], [2]]
  

• size is 2:

  p = []
  [0, 1, 2].repeated_permutation(2) {|permutation| p.push(permutation) }
  p # => [[0, 0], [0, 1], [0, 2], [1, 0], [1, 1], [1, 2], [2, 0], [2, 1], [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_permutation(-1) {|permutation| fail 'Cannot happen' }

With no block given, returns a new Enumerator.

Related: see Methods for Combining.

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.

Requests a connection to be made on the given remote_sockaddr after O_NONBLOCK is set for the underlying file descriptor. Returns 0 if successful, otherwise an exception is raised.

Parameter

• remote_sockaddr - the struct sockaddr contained in a string or Addrinfo object

Example:

# Pull down Google's web page
require 'socket'
include Socket::Constants
socket = Socket.new(AF_INET, SOCK_STREAM, 0)
sockaddr = Socket.sockaddr_in(80, 'www.google.com')
begin # emulate blocking connect
  socket.connect_nonblock(sockaddr)
rescue IO::WaitWritable
  IO.select(nil, [socket]) # wait 3-way handshake completion
  begin
    socket.connect_nonblock(sockaddr) # check connection failure
  rescue Errno::EISCONN
  end
end
socket.write("GET / HTTP/1.0\r\n\r\n")
results = socket.read

Refer to Socket#connect for the exceptions that may be thrown if the call to connect_nonblock fails.

Socket#connect_nonblock may raise any error corresponding to connect(2) failure, including Errno::EINPROGRESS.

If the exception is Errno::EINPROGRESS, it is extended by IO::WaitWritable. So IO::WaitWritable can be used to rescue the exceptions for retrying connect_nonblock.

By specifying a keyword argument exception to false, you can indicate that connect_nonblock should not raise an IO::WaitWritable exception, but return the symbol :wait_writable instead.

See

• Socket#connect