rewrite to actually use pulldown idiomatically

src/main.rs

@@ -407,7 +407,7 @@ fn update_garden<P: AsRef<Path>>(
         let mut file_string = String::new();
         file.read_to_string(&mut file_string)?;
         let markdown_source = preprocess_markdown(file_string);
-        let result = GardenParser::parse(&markdown_source)?;
+        let result = parse_garden(&markdown_source)?;
 
         pages.insert(
             String::from(path.to_str().unwrap()),
@@ -435,66 +435,48 @@ fn update_garden<P: AsRef<Path>>(
     Ok(result)
 }
 
-struct GardenParser<'a> {
-    parser: Parser<'a>,
-    last_nontext_event: Option<Event<'a>>,
-    current_top_heading: u32,
-    top_heading_text: &'a mut Option<String>,
-    links: &'a mut Vec<String>,
-}
-
 struct ParseResult {
     html: String,
     title: Option<String>,
     links: Vec<String>,
 }
 
-impl<'a> GardenParser<'a> {
-    fn parse<S: AsRef<str>>(text: &'a S) -> anyhow::Result<ParseResult> {
-        let mut title: Option<String> = None;
-        let mut links: Vec<String> = vec![];
+fn parse_garden<S: AsRef<str>>(text: S) -> anyhow::Result<ParseResult> {
+    let mut current_top_heading = 999;
+    let mut top_heading_text: Option<String> = None;
 
-        let parser = GardenParser {
-            parser: Parser::new_ext(text.as_ref(), Options::all()),
-            last_nontext_event: None,
-            current_top_heading: 999,
-            top_heading_text: &mut title,
-            links: &mut links,
-        };
+    let mut last_nontext_event: Option<Event> = None;
 
-        let mut html = String::new();
-        html::push_html(&mut html, parser);
-        html = postprocess_html(html)?;
+    let mut links: Vec<String> = vec![];
 
-        Ok(ParseResult { html, title, links })
-    }
-}
-
-impl<'a> Iterator for GardenParser<'a> {
-    type Item = Event<'a>;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        let event = self.parser.next();
-
-        if let Some(event) = &event {
-            if let Event::Start(Tag::Link(_, str, _)) = &event {
-                self.links.push(str.to_string());
-            }
-
-            if let Some(Event::Start(Tag::Heading(hl))) = self.last_nontext_event {
-                if hl < self.current_top_heading {
-                    self.current_top_heading = hl;
-                    if let Event::Text(str) = &event {
-                        *self.top_heading_text = Some(str.clone().into_string());
-                    }
-                }
-            }
-
-            self.last_nontext_event = Some(event.clone());
+    let parser = Parser::new_ext(text.as_ref(), Options::all()).map(|event| {
+        if let Event::Start(Tag::Link(_, str, _)) = &event {
+            links.push(str.to_string());
         }
 
+        if let Some(Event::Start(Tag::Heading(hl))) = last_nontext_event {
+            if hl < current_top_heading {
+                current_top_heading = hl;
+                if let Event::Text(str) = &event {
+                    top_heading_text = Some(str.clone().into_string());
+                }
+            }
+        }
+
+        last_nontext_event = Some(event.clone());
+
         event
-    }
+    });
+
+    let mut html = String::new();
+    html::push_html(&mut html, parser);
+    html = postprocess_html(html)?;
+
+    Ok(ParseResult {
+        html,
+        title: top_heading_text,
+        links,
+    })
 }
 
 fn preprocess_markdown(string: String) -> String {