From: "kddnewton (Kevin Newton) via ruby-core" <ruby-core@...> Date: 2024-05-23T17:39:47+00:00 Subject: [ruby-core:117987] [Ruby master Bug#20478] Circular parameter syntax error rules Issue #20478 has been updated by kddnewton (Kevin Newton). Also: ```ruby def foo(bar = -> { bar }) end def foo(bar = ->( ) { bar }) end def foo(bar = ->(_) { bar }) end ``` Two of these are a syntax error, but I think either all of them should be or none of them should be. ---------------------------------------- Bug #20478: Circular parameter syntax error rules https://bugs.ruby-lang.org/issues/20478#change-108411 * Author: kddnewton (Kevin Newton) * Status: Open * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- I would like to revisit https://bugs.ruby-lang.org/issues/16343. These cases are syntax errors: ```ruby def foo(bar = -> { bar }) end # no lambda parameters def foo(bar = ->() { bar }) end # no lambda parameters def foo(bar = baz { bar }) end # no block parameters def foo(bar = baz { _1 + bar }) end # parameters, but no pipes def foo(bar = baz { it + bar }) end # parameters, but no pipes ``` These cases are not syntax errors: ```ruby def foo(bar = ->(baz) { bar }) end # lambda parameters def foo(bar = baz { || bar }) end # no block parameters but empty pipes def foo(bar = baz { |qux| bar }) end # block parameters ``` I don't think these rules are very intuitive, and they feel somewhat arbitrary. I would like to suggest we change them to be either: * Syntax error is raised if the parameter is ever read in its default value at any scope depth * Syntax error is raised if the parameter is ever read in its default value at depth 0 Either one is fine by me, but gating the syntax error based on the presence of pipes is really confusing. -- https://bugs.ruby-lang.org/ ______________________________________________ ruby-core mailing list -- ruby-core@ml.ruby-lang.org To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org ruby-core info -- https://ml.ruby-lang.org/mailman3/postorius/lists/ruby-core.ml.ruby-lang.org/