Results for: "slice"

UNIXServer#accept_nonblock

Accepts an incoming connection using accept(2) after O_NONBLOCK is set for the underlying file descriptor. It returns an accepted UNIXSocket for the incoming connection.

Example

require 'socket'
serv = UNIXServer.new("/tmp/sock")
begin # emulate blocking accept
  sock = serv.accept_nonblock
rescue IO::WaitReadable, Errno::EINTR
  IO.select([serv])
  retry
end
# sock is an accepted socket.

Refer to Socket#accept for the exceptions that may be thrown if the call to UNIXServer#accept_nonblock fails.

UNIXServer#accept_nonblock may raise any error corresponding to accept(2) failure, including Errno::EWOULDBLOCK.

If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED or Errno::EPROTO, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying accept_nonblock.

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

See

StringIO#each_line

Calls the block with each remaining line read from the stream; does nothing if already at end-of-file; returns self. See Line IO.

StringScanner#initialize_copy

Returns a shallow copy of self; the [stored string] in the copy is the same string as in self.

BasicObject#instance_eval

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

BasicObject#instance_exec

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

Hash#initialize_copy

Replaces the entire contents of self with the contents of other_hash; returns self:

h = {foo: 0, bar: 1, baz: 2}
h.replace({bat: 3, bam: 4}) # => {bat: 3, bam: 4}

Related: see Methods for Assigning.

ARGF#each_line

Returns an enumerator which iterates over each line (separated by sep, which defaults to your platform’s newline character) of each file in ARGV. If a block is supplied, each line in turn will be yielded to the block, otherwise an enumerator is returned. The optional limit argument is an Integer specifying the maximum length of each line; longer lines will be split according to this limit.

This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last line of the first file has been returned, the first line of the second file is returned. The ARGF.filename and ARGF.lineno methods can be used to determine the filename of the current line and line number of the whole input, respectively.

For example, the following code prints out each line of each named file prefixed with its line number, displaying the filename once per file:

ARGF.each_line do |line|
  puts ARGF.filename if ARGF.file.lineno == 1
  puts "#{ARGF.file.lineno}: #{line}"
end

While the following code prints only the first file’s name at first, and the contents with line number counted through all named files.

ARGF.each_line do |line|
  puts ARGF.filename if ARGF.lineno == 1
  puts "#{ARGF.lineno}: #{line}"
end

ARGF#inplace_mode

Returns the file extension appended to the names of backup copies of modified files under in-place edit mode. This value can be set using ARGF.inplace_mode= or passing the -i switch to the Ruby binary.

ARGF#inplace_mode=

Sets the filename extension for in-place editing mode to the given String. The backup copy of each file being edited has this value appended to its filename.

For example:

$ ruby argf.rb file.txt

ARGF.inplace_mode = '.bak'
ARGF.each_line do |line|
  print line.sub("foo","bar")
end

First, file.txt.bak is created as a backup copy of file.txt. Then, each line of file.txt has the first occurrence of “foo” replaced with “bar”.

IPAddr#link_local?

Returns true if the ipaddr is a link-local address. IPv4 addresses in 169.254.0.0/16 reserved by RFC 3927 and link-local IPv6 Unicast Addresses in fe80::/10 reserved by RFC 4291 are considered link-local. Link-local IPv4 addresses in the IPv4-mapped IPv6 address range are also considered link-local.

IPAddr#coerce_other

No documentation available

PP::singleline_pp

Outputs obj to out like PP.pp but with no indent and newline.

PP.singleline_pp returns out.

PrettyPrint::singleline_format

This is similar to PrettyPrint::format but the result has no breaks.

maxwidth, newline and genspace are ignored.

The invocation of breakable in the block doesn’t break a line and is treated as just an invocation of text.

WeakRef#weakref_alive?

Returns true if the referenced object is still alive.

Binding#source_location

Returns the Ruby source filename and line number of the binding object.

Proc#source_location

Returns the location where the Proc was defined. The returned Array contains:

(1) the Ruby source filename
(2) the line number where the definition starts
(3) the column number where the definition starts
(4) the line number where the definition ends
(5) the column number where the definitions ends

This method will return nil if the Proc was not defined in Ruby (i.e. native).

Method#source_location

Returns the location where the method was defined. The returned Array contains:

(1) the Ruby source filename
(2) the line number where the definition starts
(3) the column number where the definition starts
(4) the line number where the definition ends
(5) the column number where the definitions ends

This method will return nil if the method was not defined in Ruby (i.e. native).

UnboundMethod#source_location

Returns the location where the method was defined. The returned Array contains:

(1) the Ruby source filename
(2) the line number where the definition starts
(3) the column number where the definition starts
(4) the line number where the definition ends
(5) the column number where the definitions ends

This method will return nil if the method was not defined in Ruby (i.e. native).

Thread#backtrace_locations

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.

TracePoint#raised_exception

Returns the exception raised on the :raise event or rescued on the :rescue event.

TracePoint#instruction_sequence

Returns the compiled instruction sequence represented by a RubyVM::InstructionSequence instance on the :script_compiled event.

Note that this method is CRuby-specific.

Kernel#trace_var

Controls tracing of assignments to global variables. The parameter symbol identifies the variable (as either a string name or a symbol identifier). cmd (which may be a string or a Proc object) or block is executed whenever the variable is assigned. The block or Proc object receives the variable’s new value as a parameter. Also see untrace_var.

trace_var :$_, proc {|v| puts "$_ is now '#{v}'" }
$_ = "hello"
$_ = ' there'

produces:

$_ is now 'hello'
$_ is now ' there'