Contents

require 'facet/kernel/constant'

class Module

  # <em>Note: the following documentation uses "class" because it's more common, but it
  # applies to modules as well.</em>
  #
  # Given the _name_ of a class, returns the class itself (i.e. instance of Class).  The
  # dereferencing starts at Object.  That is,
  #
  #   Class.by_name("String")
  #
  # is equivalent to
  #
  #   Object.const_get("String")
  #
  # The parameter _name_ is expected to be a Symbol or String, or at least to respond to
  # <tt>to_str</tt>.
  #
  # An ArgumentError is raised if _name_ does not correspond to an existing class.  If _name_
  # is not even a valid class name, the error you'll get is not defined.
  #
  # Examples:
  #
  #   Class.by_name("String")             # -> String
  #   Class.by_name("::String")           # -> String
  #   Class.by_name("Process::Sys")       # -> Process::Sys
  #   Class.by_name("GorillaZ")           # -> (ArgumentError)
  #
  #   Class.by_name("Enumerable")         # -> Enumerable
  #   Module.by_name("Enumerable")        # -> Enumerable
  #
  #--
  # Credit for this goes to Gavin Sinclair
  #++
  def by_name(name)
    result = Object.constant(name)
    return result if result.kind_of?( Module )
    raise ArgumentError, "#{name} is not a module or class"
  end

end



#  _____         _
# |_   _|__  ___| |_
#   | |/ _ \/ __| __|
#   | |  __/\__ \ |_
#   |_|\___||___/\__|
#
=begin test

  require 'test/unit'

  class TCModule < Test::Unit::TestCase

    def test_by_name
      c = ::Test::Unit::TestCase.name
      assert_equal( ::Test::Unit::TestCase, Module.by_name(c) )
      c = "Test::Unit::TestCase"
      assert_equal( ::Test::Unit::TestCase, Class.by_name(c) )
    end

  end

=end

Version data entries

22 entries across 22 versions & 1 rubygems

Version	Path
facets-1.8.20	lib/facets/core/module/by_name.rb
facets-1.8.8	lib/facets/core/module/by_name.rb