In Files

  • resolv.rb



A representation of a DNS name.

Public Class Methods

create(arg) click to toggle source

Creates a new DNS name from arg. arg can be:


returns arg.


Creates a new Name.

               # File resolv.rb, line 1047
def self.create(arg)
  case arg
  when Name
    return arg
  when String
    return, /\.\z/ =~ arg ? true : false)
    raise"cannot interpret as DNS name: #{arg.inspect}")

Public Instance Methods

absolute?() click to toggle source

True if this name is absolute.

               # File resolv.rb, line 1070
def absolute?
  return @absolute
subdomain_of?(other) click to toggle source

Returns true if other is a subdomain.


domain = Resolv::DNS::Name.create("y.z")
p Resolv::DNS::Name.create("w.x.y.z").subdomain_of?(domain) #=> true
p Resolv::DNS::Name.create("x.y.z").subdomain_of?(domain) #=> true
p Resolv::DNS::Name.create("y.z").subdomain_of?(domain) #=> false
p Resolv::DNS::Name.create("z").subdomain_of?(domain) #=> false
p Resolv::DNS::Name.create("x.y.z.").subdomain_of?(domain) #=> false
p Resolv::DNS::Name.create("w.z").subdomain_of?(domain) #=> false
               # File resolv.rb, line 1095
def subdomain_of?(other)
  raise ArgumentError, "not a domain name: #{other.inspect}" unless Name === other
  return false if @absolute != other.absolute?
  other_len = other.length
  return false if @labels.length <= other_len
  return @labels[-other_len, other_len] == other.to_a
to_s() click to toggle source

returns the domain name as a string.

The domain name doesn’t have a trailing dot even if the name object is absolute.


p Resolv::DNS::Name.create("x.y.z.").to_s #=> "x.y.z"
p Resolv::DNS::Name.create("x.y.z").to_s #=> "x.y.z"
               # File resolv.rb, line 1130
def to_s
  return @labels.join('.')

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