Rule Element Labels not supported in ANTLR4 Ruby target

[zakjan]

Generating Ruby target with Rule Element Labels leads to invalid Ruby code.

ifStmt : IF logicalExpression THEN ifBranchStmt+=stmt+ (ELSE elseBranchStmt+=stmt+)? END_IF ';' ;

->

invalid assignment

		attr_accessor :stmt = nil
		attr_accessor :ifBranchStmt = []
		attr_accessor :elseBranchStmt = []

invalid overload

				((IfStmtContext)_localctx).stmt = stmt()
				((IfStmtContext)_localctx).ifBranchStmt.push(((IfStmtContext)_localctx).stmt);

					((IfStmtContext)_localctx).stmt = stmt()
					((IfStmtContext)_localctx).elseBranchStmt.push(((IfStmtContext)_localctx).stmt);

However, simply removing them manually is not enough. There is more to it. I'm investigating.

full output

	 class IfStmtContext < Antlr4::Runtime::ParserRuleContext
		attr_accessor :stmt = nil
		attr_accessor :ifBranchStmt = []
		attr_accessor :elseBranchStmt = []
		def IF()
		  return token(ExpressParser::IF, 0)
		end
		def logicalExpression()
			return rule_context("LogicalExpressionContext",0)
		end
		def THEN()
		  return token(ExpressParser::THEN, 0)
		end
		def END_IF()
		  return token(ExpressParser::END_IF, 0)
		end
		def ELSE()
		  return token(ExpressParser::ELSE, 0)
		end
		def stmt()
			return rule_contexts("StmtContext")
		end
		def stmt_i( i)
			return rule_context("StmtContext",i)
		end
		def initialize( parent,  invokingState)
			super(parent, invokingState)
		end
		def getRuleIndex()
		 return RULE_ifStmt
		end

		def accept(visitor)
			if ( visitor.respond_to?(:visitIfStmt) )
			  return visitor.visitIfStmt(self)
			else
			 return visitor.visit_children(self)
			end
		end
	end

	def ifStmt()
		_localctx =  IfStmtContext.new(@_ctx, @_state_number)
		enter_rule(_localctx, 166, RULE_ifStmt)
		_la = 0
		begin
			enter_outer_alt(_localctx, 1)

			@_state_number = 879
			match(IF)
			@_state_number = 880
			logicalExpression()
			@_state_number = 881
			match(THEN)
			@_state_number = 883 
			@_err_handler.sync(self)
			_la = @_input.la(1)
			loop do


				@_state_number = 882
				((IfStmtContext)_localctx).stmt = stmt()
				((IfStmtContext)_localctx).ifBranchStmt.push(((IfStmtContext)_localctx).stmt);
				@_state_number = 885 
				@_err_handler.sync(self)
				_la = @_input.la(1)
			 break if (!( (((_la) & ~0x3f) == 0 && ((1 << _la) & ((1 << T__0) | (1 << ALIAS) | (1 << BEGIN_) | (1 << CASE))) != 0) || ((((_la - 71)) & ~0x3f) == 0 && ((1 << (_la - 71)) & ((1 << (ESCAPE - 71)) | (1 << (IF - 71)) | (1 << (INSERT - 71)) | (1 << (REMOVE - 71)) | (1 << (REPEAT - 71)) | (1 << (RETURN - 71)) | (1 << (SKIP_ - 71)))) != 0) || _la==SimpleId) )
			end
			@_state_number = 893
			@_err_handler.sync(self)
			_la = @_input.la(1)
			if (_la==ELSE)

				@_state_number = 887
				match(ELSE)
				@_state_number = 889 
				@_err_handler.sync(self)
				_la = @_input.la(1)
				loop do


					@_state_number = 888
					((IfStmtContext)_localctx).stmt = stmt()
					((IfStmtContext)_localctx).elseBranchStmt.push(((IfStmtContext)_localctx).stmt);
					@_state_number = 891 
					@_err_handler.sync(self)
					_la = @_input.la(1)
				 break if (!( (((_la) & ~0x3f) == 0 && ((1 << _la) & ((1 << T__0) | (1 << ALIAS) | (1 << BEGIN_) | (1 << CASE))) != 0) || ((((_la - 71)) & ~0x3f) == 0 && ((1 << (_la - 71)) & ((1 << (ESCAPE - 71)) | (1 << (IF - 71)) | (1 << (INSERT - 71)) | (1 << (REMOVE - 71)) | (1 << (REPEAT - 71)) | (1 << (RETURN - 71)) | (1 << (SKIP_ - 71)))) != 0) || _la==SimpleId) )
				end
			end

			@_state_number = 895
			match(END_IF)
			@_state_number = 896
			match(T__0)
		rescue Antlr4::Runtime::RecognitionException => re
			_localctx.exception = re
			@_err_handler.report_error(self, re)
			@_err_handler.recover(self, re)
		ensure
			exit_rule()
		end
		return _localctx
	end