
Issue #19520 has been updated by ioquatix (Samuel Williams).
OTOH, I feel it's enough to get the file:line from the backtrace to investigate/debug/fix when a NoMethodError or similar happens with such an instance of an anonymous class.
This isn't just about exception messages. Any time such an object is printed, e.g. via `irb`, a log message, any kind of formatted output, it is less informative without the proposed feature. ---------------------------------------- Feature #19520: Support for `Module.new(name)` and `Class.new(superclass, name)`. https://bugs.ruby-lang.org/issues/19520#change-103152 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- See <https://bugs.ruby-lang.org/issues/19450> for previous discussion and motivation. [This proposal](https://github.com/ruby/ruby/pull/7376) introduces the `name` parameter to `Class.new` and `Module.new`: ```ruby Class.new(superclass, name) Module.new(name) ``` As a slight change, we could use keyword arguments instead. ## Example usage The current Ruby test suite has code which shows the usefulness of this new method: ```ruby def labeled_module(name, &block) Module.new do singleton_class.class_eval { define_method(:to_s) {name} alias inspect to_s alias name to_s } class_eval(&block) if block end end module_function :labeled_module def labeled_class(name, superclass = Object, &block) Class.new(superclass) do singleton_class.class_eval { define_method(:to_s) {name} alias inspect to_s alias name to_s } class_eval(&block) if block end end module_function :labeled_class ``` The updated code would look like this: ```ruby def labeled_module(name, &block) Module.new(name, &block) end def labeled_class(name, superclass = Object, &block) Class.new(superclass, name, &block) end module_function :labeled_class ``` -- https://bugs.ruby-lang.org/