# File lib/chef/version_constraint.rb, line 28
    def initialize(constraint_spec=DEFAULT_CONSTRAINT)
      case constraint_spec
      when nil
        parse(DEFAULT_CONSTRAINT)
      when Array
        parse_from_array(constraint_spec)
      when String
        parse(constraint_spec)
      else
        msg = "VersionConstraint should be created from a String. You gave: #{constraint_spec.inspect}"
        raise Chef::Exceptions::InvalidVersionConstraint, msg
      end
    end