[ruby-core:94108] [Ruby master Feature#16037] Allow multiple single-splatted variables in `in` pattern matching and introduce non-greedy-splatted variables
From:
sawadatsuyoshi@...
Date:
2019-08-02 11:50:31 UTC
List:
ruby-core #94108
Issue #16037 has been reported by sawa (Tsuyoshi Sawada). ---------------------------------------- Feature #16037: Allow multiple single-splatted variables in `in` pattern matching and introduce non-greedy-splatted variables https://bugs.ruby-lang.org/issues/16037 * Author: sawa (Tsuyoshi Sawada) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- Pattern matching in `in` argument seems to prohibit multiple occurrences of single/double-splatted variables. ```ruby case ""; in *foo, bar; end # >> NoMatchingPatternError (Not SyntaxError) case ""; in *foo, *bar; end # >> SyntaxError: unexpected * ``` However, unlike conventional constant/variable assignment, it makes sense to have multiple occurrences of single/double-splatted variables in a single pattern matching provided that we have a definite rule regarding whether the splats are greedy or not. I propose the following. 1. Relax the syntax for pattern matching in `in` argument to allow multiple occurrences of single/double-splatted variables, and set up a rule regarding whether the splats are greedy or not; preferably greedy. 2. Further, introduce new syntax for non-greedy splats `*?foo`, `**?foo`. Currently, they are syntactically invalid, so I don't think they would conflict with existing code. -- 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>