//	)
type LineBlock struct {
	Comments
	Start  Position
	LParen LParen
	Token  []string
	Line   []*Line
	RParen RParen
}

func (x *LineBlock) Span() (start, end Position) {
	return x.Start, x.RParen.Pos.add(")")
}

// An LParen represents the beginning of a parenthesized line block.
// It is a place to store suffix comments.
type LParen struct {
	Comments
	Pos Position
}

	case token.MAP:
		return p.parseMapType()
	case token.CHAN, token.ARROW:
		return p.parseChanType()
	case token.LPAREN:
		lparen := p.pos
		p.next()
		typ := p.parseType()
		rparen := p.expect(token.RPAREN)
		return &ast.ParenExpr{Lparen: lparen, X: typ, Rparen: rparen}
	}

	// no type found
	return nil
}

		d.Specs = specs

		// Deduping can leave a blank line before the rparen; clean that up.
		if len(d.Specs) > 0 {
			lastSpec := d.Specs[len(d.Specs)-1]
			lastLine := lineAt(fset, lastSpec.Pos())
			rParenLine := lineAt(fset, d.Rparen)
			for rParenLine > lastLine+1 {
				rParenLine--
				fset.File(d.Rparen).MergeLine(rParenLine)
			}
		}
	}
}

	EQL    // ==
	LSS    // <
	GTR    // >
	ASSIGN // =
	NOT    // !

	NEQ      // !=
	LEQ      // <=
	GEQ      // >=
	DEFINE   // :=
	ELLIPSIS // ...

	LPAREN // (
	LBRACK // [
	LBRACE // {
	COMMA  // ,
	PERIOD // .

	RPAREN    // )
	RBRACK    // ]
	RBRACE    // }
	SEMICOLON // ;
	COLON     // :
	operator_end

	keyword_beg
	// Keywords
	BREAK
	CASE
	CHAN
	CONST

	if p.trace {
		defer un(trace(p, "Parameters"))
	}

	var params []*ast.Field
	lparen := p.expect(token.LPAREN)
	if p.tok != token.RPAREN {
		params = p.parseParameterList(scope, ellipsisOk)
	}
	rparen := p.expect(token.RPAREN)

	return &ast.FieldList{lparen, params, rparen}
}

func (p *parser) parseResult(scope *ast.Scope) *ast.FieldList {
	if p.trace {

		// types require parentheses around the type.
		paren := false
		switch t := x.Fun.(type) {
		case *ast.FuncType:
			paren = true
		case *ast.ChanType:
			paren = t.Dir == ast.RECV
		}
		if paren {
			p.print(token.LPAREN)
		}
		wasIndented := p.possibleSelectorExpr(x.Fun, token.HighestPrec, depth)
		if paren {
			p.print(token.RPAREN)
		}

		p.setPos(x.Lparen)
		p.print(token.LPAREN)

							return gen, true
						}
					}
				}
			}
		}
	}
	return "", false
}

// Unparen returns the expression with any enclosing parentheses removed.
func Unparen(e Expr) Expr {
	for {
		paren, ok := e.(*ParenExpr)
		if !ok {
			return e
		}
		e = paren.X
	}

	case *CommentBlock:
		// done

	case *LParen:
		p.printf("(")
	case *RParen:
		p.printf(")")

	case *Line:
		p.tokens(x.Token)

	case *LineBlock:
		p.tokens(x.Token)
		p.printf(" ")
		p.expr(&x.LParen)
		p.margin++
		for _, l := range x.Line {
			p.newline()
			p.expr(l)
		}
		p.margin--
		p.newline()
		p.expr(&x.RParen)
	}

					if isIdent(n.Args[0], "pos") {
						pos := n.Args[0].Pos()
						fun := &ast.SelectorExpr{X: newIdent(pos, "posn"), Sel: newIdent(pos, "Pos")}
						arg := &ast.CallExpr{Fun: fun, Lparen: pos, Args: nil, Ellipsis: token.NoPos, Rparen: pos}
						n.Args[0] = arg
						return false
					}
				case "addf":
					// rewrite err.addf(pos, ...) to err.addf(posn, ...)
					if isIdent(n.Args[0], "pos") {

func dddErrPos(call *ast.CallExpr) positioner { return atPos(call.Ellipsis) }

// argErrPos returns positioner for reporting an invalid argument count.
func argErrPos(call *ast.CallExpr) positioner { return inNode(call, call.Rparen) }

// startPos returns the start position of node n.
func startPos(n ast.Node) token.Pos { return n.Pos() }

// endPos returns the position of the first character immediately after node n.