if n.Init != nil {
				r.openScope(n.Tag.Pos())
				defer r.closeScope()
			}
			ast.Walk(r, n.Tag)
		}
		if n.Body != nil {
			r.walkStmts(n.Body.List)
		}

	case *ast.TypeSwitchStmt:
		if n.Init != nil {
			r.openScope(n.Pos())
			defer r.closeScope()
			ast.Walk(r, n.Init)
		}
		r.openScope(n.Assign.Pos())
		defer r.closeScope()
		ast.Walk(r, n.Assign)

			check.errorf(s, InvalidSyntaxTree, "branch statement: %s", s.Tok)
		}

	case *ast.BlockStmt:
		check.openScope(s, "block")
		defer check.closeScope()

		check.stmtList(inner, s.List)

	case *ast.IfStmt:
		check.openScope(s, "if")
		defer check.closeScope()

		check.simpleStmt(s.Init)
		var x operand
		check.expr(nil, &x, s.Cond)
		if x.mode != invalid && !allBoolean(x.typ) {

			check.errorf(s, InvalidSyntaxTree, "branch statement: %s", s.Tok)
		}

	case *syntax.BlockStmt:
		check.openScope(s, "block")
		defer check.closeScope()

		check.stmtList(inner, s.List)

	case *syntax.IfStmt:
		check.openScope(s, "if")
		defer check.closeScope()

		check.simpleStmt(s.Init)
		var x operand
		check.expr(nil, &x, s.Cond)
		if x.mode != invalid && !allBoolean(x.typ) {

	list := p.parseStmtList()
	p.closeLabelScope()
	p.closeScope()
	rbrace := p.expect(token.RBRACE)

	return &ast.BlockStmt{lbrace, list, rbrace}
}

func (p *parser) parseBlockStmt() *ast.BlockStmt {
	if p.trace {
		defer un(trace(p, "BlockStmt"))
	}

	lbrace := p.expect(token.LBRACE)
	p.openScope()
	list := p.parseStmtList()
	p.closeScope()
	rbrace := p.expect(token.RBRACE)

	check.openScope(ftyp, "function")
	check.scope.isFunc = true
	check.recordScope(ftyp, check.scope)
	sig.scope = check.scope
	defer check.closeScope()

	if recvPar != nil {
		// collect generic receiver type parameters, if any
		// - a receiver type parameter is like any other type parameter, except that it is declared implicitly

	check.openScope(ftyp, "function")
	check.scope.isFunc = true
	check.recordScope(ftyp, check.scope)
	sig.scope = check.scope
	defer check.closeScope()

	if recvPar != nil && len(recvPar.List) > 0 {
		// collect generic receiver type parameters, if any
		// - a receiver type parameter is like any other type parameter, except that it is declared implicitly

					check.error(tdecl, UnsupportedFeature, "generic type alias requires GOEXPERIMENT=aliastypeparams")
					versionErr = true
				}
				check.openScope(tdecl, "type parameters")
				defer check.closeScope()
				check.collectTypeParams(&alias.tparams, tdecl.TParamList)
			}

			rhs = check.definedType(tdecl.Type, obj)
			assert(rhs != nil)
			alias.fromRHS = rhs
			Unalias(alias) // resolve alias.actual

					check.error(tdecl, UnsupportedFeature, "generic type alias requires GOEXPERIMENT=aliastypeparams")
					versionErr = true
				}
				check.openScope(tdecl, "type parameters")
				defer check.closeScope()
				check.collectTypeParams(&alias.tparams, tdecl.TypeParams)
			}

			rhs = check.definedType(tdecl.Type, obj)
			assert(rhs != nil)
			alias.fromRHS = rhs
			Unalias(alias) // resolve alias.actual