creates a new Socket connected to the address of local_addrinfo.

If local_addrinfo is nil, the address of the socket is not bound.

The timeout specify the seconds for timeout. Errno::ETIMEDOUT is raised when timeout occur.

If a block is given the created socket is yielded for each address.

creates a socket connected to the address of self.

If one or more arguments given as local_addr_args, it is used as the local address of the socket. local_addr_args is given for family_addrinfo to obtain actual address.

If local_addr_args is not given, the local address of the socket is not bound.

The optional last argument opts is options represented by a hash. opts may have following options:

:timeout

specify the timeout in seconds.

If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.

Addrinfo.tcp("www.ruby-lang.org", 80).connect_from("0.0.0.0", 4649) {|s|
  s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
  puts s.read
}

# Addrinfo object can be taken for the argument.
Addrinfo.tcp("www.ruby-lang.org", 80).connect_from(Addrinfo.tcp("0.0.0.0", 4649)) {|s|
  s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
  puts s.read
}

creates a socket connected to remote_addr_args and bound to self.

The optional last argument opts is options represented by a hash. opts may have following options:

:timeout

specify the timeout in seconds.

If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.

Addrinfo.tcp("0.0.0.0", 4649).connect_to("www.ruby-lang.org", 80) {|s|
  s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n"
  puts s.read
}

Evaluates a string containing Ruby source code, or the given block, within the context of the receiver (obj). In order to set the context, the variable self is set to obj while the code is executing, giving the code access to obj’s instance variables and private methods.

When instance_eval is given a block, obj is also passed in as the block’s only argument.

When instance_eval is given a String, the optional second and third parameters supply a filename and starting line number that are used when reporting compilation errors.

class KlassWithSecret
  def initialize
    @secret = 99
  end
  private
  def the_secret
    "Ssssh! The secret is #{@secret}."
  end
end
k = KlassWithSecret.new
k.instance_eval { @secret }          #=> 99
k.instance_eval { the_secret }       #=> "Ssssh! The secret is 99."
k.instance_eval {|obj| obj == self } #=> true

Executes the given block within the context of the receiver (obj). In order to set the context, the variable self is set to obj while the code is executing, giving the code access to obj’s instance variables. Arguments are passed as block parameters.

class KlassWithSecret
  def initialize
    @secret = 99
  end
end
k = KlassWithSecret.new
k.instance_exec(5) {|x| @secret+x }   #=> 104

Set options. Takes the same argument as GetoptLong.new.

Raises a RuntimeError if option processing has already started.

Raises PStore::Error if the calling code is not in a PStore#transaction.

List of options that will be supplied to RDoc

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.

Returns the current execution stack—an array containing backtrace location objects.

See Thread::Backtrace::Location for more information.

The optional start parameter determines the number of initial stack entries to omit from the top of the stack.

A second optional length parameter can be used to limit how many entries are returned from the stack.

Returns nil if start is greater than the size of current execution stack.

Optionally you can pass a range, which will return an array containing the entries within the specified range.

Creates a new MonitorMixin::ConditionVariable associated with the Monitor object.

Returns garbage collector generation for the given object.

class B
  include ObjectSpace

  def foo
    trace_object_allocations do
      obj = Object.new
      p "Generation is #{allocation_generation(obj)}"
    end
  end
end

B.new.foo #=> "Generation is 3"

See ::trace_object_allocations for more information and examples.

Specifies a Proc object proc to determine completion behavior. It should take input string and return an array of completion candidates.

The default completion is used if proc is nil.

The String that is passed to the Proc depends on the Readline.completer_word_break_characters property. By default the word under the cursor is passed to the Proc. For example, if the input is “foo bar” then only “bar” would be passed to the completion Proc.

Upon successful completion the Readline.completion_append_character will be appended to the input so the user can start working on their next argument.

Examples

Completion for a Static List

require 'readline'

LIST = [
  'search', 'download', 'open',
  'help', 'history', 'quit',
  'url', 'next', 'clear',
  'prev', 'past'
].sort

comp = proc { |s| LIST.grep(/^#{Regexp.escape(s)}/) }

Readline.completion_append_character = " "
Readline.completion_proc = comp

while line = Readline.readline('> ', true)
  p line
end

Completion For Directory Contents

require 'readline'

Readline.completion_append_character = " "
Readline.completion_proc = Proc.new do |str|
  Dir[str+'*'].grep(/^#{Regexp.escape(str)}/)
end

while line = Readline.readline('> ', true)
  p line
end

Autocomplete strategies

When working with auto-complete there are some strategies that work well. To get some ideas you can take a look at the completion.rb file for irb.

The common strategy is to take a list of possible completions and filter it down to those completions that start with the user input. In the above examples Enumerator.grep is used. The input is escaped to prevent Regexp special characters from interfering with the matching.

It may also be helpful to use the Abbrev library to generate completions.

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

Returns the completion Proc object.

Returns the number of malloc() allocations.

Only available if ruby was built with CALC_EXACT_MALLOC_SIZE.

Returns the Base64-encoded version of bin. This method complies with RFC 4648. No line feeds are added.

Returns the Base64-decoded version of str. This method complies with RFC 4648. ArgumentError is raised if str is incorrectly padded or contains non-alphabet characters. Note that CR or LF are also rejected.

Set the default ACL to acl.

See DRb::DRbServer.default_acl.

Set the default ACL to acl.

See DRb::DRbServer.default_acl.

Returns an Array of option names of the method mid.

p FileUtils.options_of(:rm)  #=> ["noop", "verbose", "force"]

Takes a hash as its argument. The key is a symbol or an array of symbols. These symbols correspond to method names, instance variable names, or constant names (see def_delegator). The value is the accessor to which the methods will be delegated.

Tests for the presence of a --with-config or --without-config option. Returns true if the with option is given, false if the without option is given, and the default value otherwise.

This can be useful for adding custom definitions, such as debug information.

Example:

if with_config("debug")
   $defs.push("-DOSSL_DEBUG") unless $defs.include? "-DOSSL_DEBUG"
end