You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: render.go
    path of file: ./repos/fake-sms/vendor/golang.org/x/net/html
    
    the code of the file until where you have to start completion: // Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package html

import (
	"bufio"
	"errors"
	"fmt"
	"io"
	"strings"
)

type writer interface {
	io.Writer
	io.ByteWriter
	WriteString(string) (int, error)
}

// Render renders the parse tree n to the given writer.
//
// Rendering is done on a 'best effort' basis: calling Parse on the output of
// Render will always result in something similar to the original tree, but it
// is not necessarily an exact clone unless the original tree was 'well-formed'.
// 'Well-formed' is not easily specified; the HTML5 specification is
// complicated.
//
// Calling Parse on arbitrary input typically results in a 'well-formed' parse
// tree. However, it is possible for Parse to yield a 'badly-formed' parse tree.
// For example, in a 'well-formed' parse tree, no <a> element is a child of
// another <a> element: parsing "<a><a>" results in two sibling elements.
// Similarly, in a 'well-formed' parse tree, no <a> element is a child of a
// <table> element: parsing "<p><table><a>" results in a <p> with two sibling
// children; the <a> is reparented to the <table>'s parent. However, calling
// Parse on "<a><table><a>" does not return an error, but the result has an <a>
// element with an <a> child, and is therefore not 'well-formed'.
//
// Programmatically constructed trees are typically also 'well-formed', but it
// is possible to construct a tree that looks innocuous but, when rendered and
// re-parsed, results in a different tree. A simple example is that a solitary
// text node would become a tree containing <html>, <head> and <body> elements.
// Another example is that the programmatic equivalent of "a<head>b</head>c"
// becomes "<html><head><head/><body>abc</body></html>".
func Render(w io.Writer, n *Node) error {
	if x, ok := w.(writer); ok {
		return render(x, n)
	}
	buf := bufio.NewWriter(w)
	if err := render(buf, n); err != nil {
		return err
	}
	return buf.Flush()
}

// plaintextAbort is
    
func render1(w writer, n *Node) error {
	// Render non-element nodes; these are the easy cases.
	switch n.Type {
	case ErrorNode:
		return errors.New("html: cannot render an ErrorNode node")
	case TextNode:
		return escape(w, n.Data)
	case DocumentNode:
		for c := n.FirstChild; c != nil; c = c.NextSibling {
			if err := render1(w, c); err != nil {
				return err
			}
		}
		return nil
	case ElementNode:
		// No-op.
	case CommentNode:
		if _, err := w.WriteString("<!--"); err != nil {
			return err
		}
		if _, err := w.WriteString(n.Data); err != nil {
			return err
		}
		if _, err := w.WriteString("-->"); err != nil {
			return err
		}
		return nil
	case DoctypeNode:
		if _, err := w.WriteString("<!DOCTYPE "); err != nil {
			return err
		}
		if _, err := w.WriteString(n.Data); err != nil {
			return err
		}
		if n.Attr != nil {
			var p, s string
			for _, a := range n.Attr {
				switch a.Key {
				case "public":
					p = a.Val
				case "system":
					s = a.Val
				}
			}
			if p != "" {
				if _, err := w.WriteString(" PUBLIC "); err != nil {
					return err
				}
				if err := writeQuoted(w, p); err != nil {
					return err
				}
				if s != "" {
					if err := w.WriteByte(' '); err != nil {
						return err
					}
					if err := writeQuoted(w, s); err != nil {
						return err
					}
				}
			} else if s != "" {
				if _, err := w.WriteString(" SYSTEM "); err != nil {
					return err
				}
				if err := writeQuoted(w, s); err != nil {
					return err
				}
			}
		}
		return w.WriteByte('>')
	default:
		return errors.New("html: unknown node type")
	}

	// Render the <xxx> opening tag.
	if err := w.WriteByte('<'); err != nil {
		return err
	}
	if _, err := w.WriteString(n.Data); err != nil {
		return err
	}
	for _, a := range n.Attr {
		if err := w.WriteByte(' '); err != nil {
			return err
		}
		if a.Namespace != "" {
			if _, err := w.WriteString(a.Namespace); err != nil {
				return err
			}
			if err := w.WriteByte(':'); err != nil {
				return err
			}
		}
		if _, err := w.WriteString(a.Key); err != nil {
			return err
		}
		if _, err := w.WriteString(`="`); err != nil {
			return err
		}
		if err := escape(w, a.Val); err != nil {
			return err
		}
		if err := w.WriteByte('"'); err != nil {
			return err
		}
	}
	if voidElements[n.Data] {
		if n.FirstChild != nil {
			return fmt.Errorf("html: void element <%s> has child nodes", n.Data)
		}
		_, err := w.WriteString("/>")
		return err
	}
	if err := w.WriteByte('>'); err != nil {
		return err
	}

	// Add initial newline where there is danger of a newline beging ignored.
	if c := n.FirstChild; c != nil && c.Type == TextNode && strings.HasPrefix(c.Data, "\n") {
		switch n.Data {
		case "pre", "listing", "textarea":
			if err := w.WriteByte('\n'); err != nil {
				return err
			}
		}
	}

	// Render any child nodes.
	switch n.Data {
	case "iframe", "noembed", "noframes", "noscript", "plaintext", "script", "style", "xmp":
		for c := n.FirstChild; c != nil; c = c.NextSibling {
			if c.Type == TextNode {
				if _, err := w.WriteString(c.Data); err != nil {
					return err
				}
			} else {
				if err := render1(w, c); err != nil {
					return err
				}
			}
		}
		if n.Data == "plaintext" {
			// Don't render anything else. <plaintext> must be the
			// last element in the file, with no closing tag.
			return plaintextAbort
		}
	default:
		for c := n.FirstChild; c != nil; c = c.NextSibling {
			if err := render1(w, c); err != nil {
				return err
			}
		}
	}

	// Render the </xxx> closing tag.
	if _, err := w.WriteString("</"); err != nil {
		return err
	}
	if _, err := w.WriteString(n.Data); err != nil {
		return err
	}
	return w.WriteByte('>')
}