blog/mataroa: remove iterators

Let's make this blog compatible to Go 1.21 at minimum.

blog.go

@@ -225,7 +225,8 @@ func genRss(ps posts) string {
 	))
 
 	var items []*feeds.Item
-	for path, post := range ps.ReverseIterator() {
+	for el := ps.Back(); el != nil; el = el.Prev() {
+		path, post := el.Key, el.Value
 		link := must1(url.JoinPath(blogMainUrl, path))
 		var buf bytes.Buffer
 		must(md.Convert(post.contents, &buf))
@@ -243,7 +244,8 @@ func genRss(ps posts) string {
 
 func genReadme(ps posts) string {
 	var titles []string
-	for path, post := range ps.ReverseIterator() {
+	for el := ps.Back(); el != nil; el = el.Prev() {
+		path, post := el.Key, el.Value
 		title := fmt.Sprintf(
 			"- [%s](%s) - %s",
 			post.title,

go.mod

@@ -1,6 +1,6 @@
 module github.com/thiagokokada/blog
 
-go 1.23
+go 1.21
 
 require (
 	github.com/elliotchance/orderedmap/v2 v2.4.0

mataroa.go

@@ -132,11 +132,12 @@ func prepareToMataroa(ps posts) posts {
 	)
 
 	preparedPosts := orderedmap.NewOrderedMap[path, post]()
-	for filename, p := range ps.Iterator() {
+	for el := ps.Front(); el != nil; el = el.Next() {
+		path, post := el.Key, el.Value
 		buf := bytes.Buffer{}
-		must(md.Convert([]byte(p.contents), &buf))
-		p.contents = buf.Bytes()
-		preparedPosts.Set(filename, p)
+		must(md.Convert([]byte(post.contents), &buf))
+		post.contents = buf.Bytes()
+		preparedPosts.Set(path, post)
 	}
 	return preparedPosts
 }
@@ -146,7 +147,8 @@ func publishToMataroa(ps posts) {
 		log.Fatal("empty MATAROA_TOKEN environment variable")
 	}
 
-	for _, post := range prepareToMataroa(ps).Iterator() {
+	for el := prepareToMataroa(ps).Front(); el != nil; el = el.Next() {
+		post := el.Value
 		p, resp := must2(getMataroaPost(post.slug))
 		var err error
 		if p.Ok {