From: "kddnewton (Kevin Newton) via ruby-core" <ruby-core@...> Date: 2024-05-20T14:05:13+00:00 Subject: [ruby-core:117943] [Ruby master Bug#20478] Circular parameter syntax error rules Issue #20478 has been updated by kddnewton (Kevin Newton). @nobu another option would be to delete those tests and leave it up to the parser instead of forcing parse.y to implement it. Specifically I'm talking about: ``` o = Object.new assert_warn("") do o.instance_eval("def foo(var: bar {| | var}) var end") end o = Object.new assert_warn("") do o.instance_eval("def foo(var: bar {|| var}) var end") end ``` and ``` o = Object.new assert_warn("") do o.instance_eval("def foo(var = bar {| | var}) var end") end o = Object.new assert_warn("") do o.instance_eval("def foo(var = bar {|| var}) var end") end ``` If it's too complicated to implement in parse.y, then removing these tests would be a good compromise. These tests themselves are the issue blocking me. ---------------------------------------- Bug #20478: Circular parameter syntax error rules https://bugs.ruby-lang.org/issues/20478#change-108360 * 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/