Issue #13196 has been updated by Robert A. Heiler. I guess the error-reporting there did not yet account for the possibility that keyword arguments can be mandatory too, so I agree that the message "wrong number of arguments (given 1, expected 0)" appears to be incorrect, since one indeed has to pass a mandatory argument to that method. I assume that when keyword args were added, this behaviour was probably not yet been noticed. I have not seen code like "foo:" in any method definition yet either, though. ---------------------------------------- Bug #13196: Improve keyword argument errors when non-keyword arguments given https://bugs.ruby-lang.org/issues/13196#change-62880 * Author: Olivier Lacan * Status: Open * Priority: Normal * Assignee: * Target version: * ruby -v: * Backport: 2.2: UNKNOWN, 2.3: UNKNOWN, 2.4: UNKNOWN ---------------------------------------- Given the following method definition: ```ruby def explode(code:) puts "Boom!" end ``` If a Ruby user doesn't provide any arguments when calling the `explode` method, the following helpful feedback is given: ```ruby explode ArgumentError: missing keyword: code ``` But when a Ruby user mistakenly provides a regular argument, the exception message is obtuse and unhelpful: ```ruby explode "1234" ArgumentError: wrong number of arguments (given 1, expected 0) ``` This does not provide information to properly recover from the error. Worse, it's incorrect. It is not true that the method expected 0 arguments. The method expected 1 keyword argument. Instead, Ruby should respond something like: ```ruby explode "1234" ArgumentError: missing keyword: code, given "1234" which is not a keyword argument. ``` One could argue that this situation would call for a different error class, perhaps a `KeywordArgumentError` that would inherit from `ArgumentError`, but that would extend the scope of this feature request a bit too far in my mind. -- https://bugs.ruby-lang.org/ Unsubscribe: <mailto:ruby-core-request / ruby-lang.org?subject=unsubscribe> <http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>