Returns any backtrace associated with the exception. This method is similar to Exception#backtrace, but the backtrace is an array of

Thread::Backtrace::Location.

Now, 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.

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.

DateTime.new(2001,2,3,12).day_fraction    #=> (1/2)

Identical to CSV#convert(), but for header rows.

Note that this method must be called before header rows are read to have any effect.

The actual work method for adding converters, used by both CSV.convert() and CSV.header_convert().

This method requires the var_name of the instance variable to place the converters in, the const Hash to lookup named converters in, and the normal parameters of the CSV.convert() and CSV.header_convert() methods.

Returns the Laplace expansion along given row or column.

Matrix[[7,6], [3,9]].laplace_expansion(column: 1)
 => 45

Matrix[[Vector[1, 0], Vector[0, 1]], [2, 3]].laplace_expansion(row: 0)
 => Vector[3, -2]

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

Returns true if the set is a proper subset of the given set.

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 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).

Builds a temporary array and traverses that array in reverse order.

If no block is given, an enumerator is returned instead.

  (1..3).reverse_each { |v| p v }

produces:

  3
  2
  1

Returns the source file origin from the given object.

See ::trace_object_allocations for more information and examples.

Returns the original line from source for from the given object.

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.

Start a dRuby server locally.

The new dRuby server will become the primary server, even if another server is currently the primary server.

uri is the URI for the server to bind to. If nil, the server will bind to random port on the default local host name and use the default dRuby protocol.

front is the server’s front object. This may be nil.

config is the configuration for the new server. This may be nil.

See DRbServer::new.

Start a dRuby server locally.

The new dRuby server will become the primary server, even if another server is currently the primary server.

uri is the URI for the server to bind to. If nil, the server will bind to random port on the default local host name and use the default dRuby protocol.

front is the server’s front object. This may be nil.

config is the configuration for the new server. This may be nil.

See DRbServer::new.

Get the ‘current’ server.

In the context of execution taking place within the main thread of a dRuby server (typically, as a result of a remote call on the server or one of its objects), the current server is that server. Otherwise, the current server is the primary server.

If the above rule fails to find a server, a DRbServerNotFound error is raised.

Get the ‘current’ server.

In the context of execution taking place within the main thread of a dRuby server (typically, as a result of a remote call on the server or one of its objects), the current server is that server. Otherwise, the current server is the primary server.

If the above rule fails to find a server, a DRbServerNotFound error is raised.