diff --git a/src/inline.rs b/src/inline.rs
index dc31507..c4e7048 100644
--- a/src/inline.rs
+++ b/src/inline.rs
@@ -97,11 +97,11 @@ impl AtomicState {
     }
 }
 
-pub struct Parser<'s> {
+pub struct Parser<I> {
     /// The last inline element has been provided, finish current events.
     last: bool,
     /// Lexer, hosting upcoming source.
-    lexer: lex::Lexer<'s>,
+    lexer: lex::Lexer<I>,
     /// Span of current event.
     span: Span,
     /// State of non-recursive elements.
@@ -116,11 +116,11 @@ pub struct Parser<'s> {
     events: std::collections::VecDeque<Event>,
 }
 
-impl<'s> Parser<'s> {
-    pub fn new() -> Self {
+impl<I: Iterator<Item = char> + Clone> Parser<I> {
+    pub fn new(chars: I) -> Self {
         Self {
-            last: false,
-            lexer: lex::Lexer::new(""),
+            last: true,
+            lexer: lex::Lexer::new(chars),
             span: Span::new(0, 0),
             atomic_state: AtomicState::None,
             typesets: Vec::new(),
@@ -129,13 +129,15 @@ impl<'s> Parser<'s> {
         }
     }
 
-    pub fn parse(&mut self, src: &'s str, last: bool) {
-        self.lexer = lex::Lexer::new(src);
+    /*
+    pub fn parse(&mut self, src: &str, last: bool) {
+        self.lexer = lex::Lexer::new(src.chars());
         if last {
             assert!(!self.last);
         }
         self.last = last;
     }
+    */
 
     fn eat(&mut self) -> Option<lex::Token> {
         let tok = self.lexer.next();
@@ -181,7 +183,8 @@ impl<'s> Parser<'s> {
                     && first.len == opener_len
                 {
                     self.atomic_state = AtomicState::None;
-                    let kind =
+                    let kind = todo!();
+                    /*
                         if matches!(kind, Verbatim) && self.lexer.peek_ahead().starts_with("{=") {
                             let mut chars = self.lexer.peek_ahead()["{=".len()..].chars();
                             let len = chars
@@ -201,6 +204,7 @@ impl<'s> Parser<'s> {
                         } else {
                             kind
                         };
+                    */
                     EventKind::Exit(kind)
                 } else {
                     EventKind::Str
@@ -261,13 +265,12 @@ impl<'s> Parser<'s> {
     }
 
     fn parse_span(&mut self, first: &lex::Token) -> Option<Event> {
-        match first.kind {
+        if let Some(open) = match first.kind {
             lex::Kind::Open(Delimiter::Bracket) => Some(true),
             lex::Kind::Close(Delimiter::Bracket) => Some(false),
             _ => None,
-        }
-        .map(|open| {
-            if open {
+        } {
+            Some(if open {
                 self.spans.push(self.events.len());
                 // use str for now, replace if closed later
                 Event {
@@ -275,21 +278,44 @@ impl<'s> Parser<'s> {
                     span: self.span,
                 }
             } else {
-                if self.lexer.peek_ahead().starts_with('[') {
+                /*
+                let kind = if self.lexer.peek_ahead().starts_with('[') {
                     let mut chars = self.lexer.peek_ahead()["[".len()..].chars();
                     let len = chars
                         .clone()
                         .take_while(|c| !c.is_whitespace() && !matches!(c, '[' | ']'))
                         .count();
                     match chars.nth(len) {
-                        Some(']') => todo!(),
-                        None => self.atomic_state = AtomicState::ReferenceLinkTag,
-                        _ => todo!(),
+                        Some(']') => EventKind::Exit(ReferenceLink),
+                        None => {
+                            self.atomic_state = AtomicState::ReferenceLinkTag;
+                            return None;
+                        }
+                        _ => EventKind::Str,
                     }
-                }
+                } else if self.lexer.peek_ahead().starts_with('(') {
+                    let mut chars = self.lexer.peek_ahead()["[".len()..].chars();
+                    let len = chars
+                        .clone()
+                        .take_while(|c| !c.is_whitespace() && !matches!(c, '[' | ']'))
+                        .count();
+                    match chars.nth(len) {
+                        Some(']') => EventKind::Exit(ReferenceLink),
+                        None => {
+                            self.atomic_state = AtomicState::Url { auto: false };
+                            return None;
+                        }
+                        _ => EventKind::Str,
+                    }
+                } else {
+                    return None;
+                };
+                    */
                 todo!()
-            }
-        })
+            })
+        } else {
+            None
+        }
     }
 
     fn parse_typeset(&mut self, first: &lex::Token) -> Option<Event> {
@@ -365,7 +391,7 @@ impl<'s> Parser<'s> {
     }
 }
 
-impl<'s> Iterator for Parser<'s> {
+impl<I: Iterator<Item = char> + Clone> Iterator for Parser<I> {
     type Item = Event;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -437,8 +463,7 @@ mod test {
     macro_rules! test_parse {
         ($($st:ident,)? $src:expr $(,$($token:expr),* $(,)?)?) => {
             #[allow(unused)]
-            let mut p = super::Parser::new();
-            p.parse($src, true);
+            let mut p = super::Parser::new($src.chars());
             let actual = p.map(|ev| (ev.kind, ev.span.of($src))).collect::<Vec<_>>();
             let expected = &[$($($token),*,)?];
             assert_eq!(actual, expected, "\n\n{}\n\n", $src);
diff --git a/src/lex.rs b/src/lex.rs
index 333d173..e12014c 100644
--- a/src/lex.rs
+++ b/src/lex.rs
@@ -82,9 +82,8 @@ impl Sequence {
 }
 
 #[derive(Clone)]
-pub(crate) struct Lexer<'s> {
-    pub src: &'s str,
-    chars: std::str::Chars<'s>,
+pub(crate) struct Lexer<I> {
+    chars: I,
     /// Next character should be escaped.
     escape: bool,
     /// Token to be peeked or next'ed.
@@ -93,11 +92,10 @@ pub(crate) struct Lexer<'s> {
     len: usize,
 }
 
-impl<'s> Lexer<'s> {
-    pub fn new(src: &'s str) -> Lexer<'s> {
+impl<I: Iterator<Item = char> + Clone> Lexer<I> {
+    pub fn new(chars: I) -> Lexer<I> {
         Lexer {
-            src,
-            chars: src.chars(),
+            chars,
             escape: false,
             next: None,
             len: 0,
@@ -111,15 +109,19 @@ impl<'s> Lexer<'s> {
         self.next.as_ref()
     }
 
+    /*
     pub fn pos(&self) -> usize {
         self.src.len()
             - self.chars.as_str().len()
             - self.next.as_ref().map(|t| t.len).unwrap_or_default()
     }
+    */
 
+    /*
     pub fn peek_ahead(&mut self) -> &'s str {
         &self.src[self.pos()..]
     }
+    */
 
     fn next_token(&mut self) -> Option<Token> {
         let mut current = self.token();
@@ -272,7 +274,7 @@ impl<'s> Lexer<'s> {
     }
 }
 
-impl<'s> Iterator for Lexer<'s> {
+impl<I: Iterator<Item = char> + Clone> Iterator for Lexer<I> {
     type Item = Token;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -290,7 +292,7 @@ mod test {
     macro_rules! test_lex {
         ($($st:ident,)? $src:expr $(,$($token:expr),* $(,)?)?) => {
             #[allow(unused)]
-            let actual = super::Lexer::new($src).collect::<Vec<_>>();
+            let actual = super::Lexer::new($src.chars()).collect::<Vec<_>>();
             let expected = vec![$($($token),*,)?];
             assert_eq!(actual, expected, "{}", $src);
         };
diff --git a/src/lib.rs b/src/lib.rs
index ced2533..483b349 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -304,20 +304,31 @@ impl<'s> Attributes<'s> {
         Self(self.0.take())
     }
 
-    #[must_use]
-    pub fn valid(src: &str) -> bool {
-        todo!()
-    }
-
     pub fn parse(&mut self, src: &'s str) {
         todo!()
     }
 }
 
+#[derive(Clone)]
+struct InlineChars<'t, 's> {
+    src: &'s str,
+    inlines: tree::Atoms<'t, block::Block, block::Atom>,
+}
+
+impl<'t, 's> Iterator for InlineChars<'t, 's> {
+    type Item = char;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        (&mut self.inlines)
+            .flat_map(|sp| sp.of(self.src).chars())
+            .next()
+    }
+}
+
 pub struct Parser<'s> {
     src: &'s str,
     tree: block::Tree,
-    parser: Option<inline::Parser<'s>>,
+    inline_parser: Option<inline::Parser<InlineChars<'s, 's>>>,
     inline_start: usize,
     block_attributes: Attributes<'s>,
 }
@@ -328,7 +339,7 @@ impl<'s> Parser<'s> {
         Self {
             src,
             tree: block::parse(src),
-            parser: None,
+            inline_parser: None,
             inline_start: 0,
             block_attributes: Attributes::none(),
         }
@@ -339,12 +350,15 @@ impl<'s> Iterator for Parser<'s> {
     type Item = Event<'s>;
 
     fn next(&mut self) -> Option<Self::Item> {
-        while let Some(parser) = &mut self.parser {
+        if let Some(parser) = &mut self.inline_parser {
             // inside leaf block, with inline content
             if let Some(mut inline) = parser.next() {
                 inline.span = inline.span.translate(self.inline_start);
                 return Some(Event::from_inline(self.src, inline));
-            } else if let Some(ev) = self.tree.next() {
+            }
+            self.inline_parser = None;
+            /*
+            else if let Some(ev) = self.tree.next() {
                 match ev.kind {
                     tree::EventKind::Atom(a) => {
                         assert_eq!(a, block::Atom::Inline);
@@ -352,12 +366,13 @@ impl<'s> Iterator for Parser<'s> {
                         parser.parse(ev.span.of(self.src), last_inline);
                     }
                     tree::EventKind::Exit(c) => {
-                        self.parser = None;
+                        self.inline_parser = None;
                         return Some(Event::End(Container::from_block(ev.span.of(self.src), c)));
                     }
                     tree::EventKind::Enter(..) => unreachable!(),
                 }
             }
+            */
         }
 
         for ev in &mut self.tree {
@@ -372,12 +387,18 @@ impl<'s> Iterator for Parser<'s> {
                         continue;
                     }
                 },
-                tree::EventKind::Enter(c) => {
-                    if matches!(c, block::Block::Leaf(_)) {
-                        self.parser = Some(inline::Parser::new());
+                tree::EventKind::Enter(b) => {
+                    if matches!(b, block::Block::Leaf(_)) {
+                        let chars = InlineChars {
+                            src: self.src,
+                            inlines: self.tree.atoms(),
+                        };
+                        // TODO solve self-referential reference here without unsafe
+                        self.inline_parser =
+                            unsafe { Some(std::mem::transmute(inline::Parser::new(chars))) };
                         self.inline_start = ev.span.end();
                     }
-                    let container = match c {
+                    let container = match b {
                         block::Block::Leaf(block::Leaf::CodeBlock { .. }) => {
                             self.inline_start += 1; // skip newline
                             Container::CodeBlock {
diff --git a/src/tree.rs b/src/tree.rs
index cd5b74b..6fa6b0c 100644
--- a/src/tree.rs
+++ b/src/tree.rs
@@ -20,6 +20,19 @@ pub struct Tree<C, A> {
     head: Option<NodeIndex>,
 }
 
+#[derive(Clone)]
+pub struct Atoms<'t, C, A> {
+    iter: std::slice::Iter<'t, Node<C, A>>,
+}
+
+impl<'t, C, A> Iterator for Atoms<'t, C, A> {
+    type Item = Span;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next().map(|n| n.span)
+    }
+}
+
 impl<C: Copy, A: Copy> Tree<C, A> {
     fn new(nodes: Vec<Node<C, A>>) -> Self {
         let head = nodes[NodeIndex::root().index()].next;
@@ -30,7 +43,15 @@ impl<C: Copy, A: Copy> Tree<C, A> {
         }
     }
 
-    pub fn atoms(&self) -> impl Iterator<Item = (A, Span)> + '_ {
+    pub fn atoms(&self) -> Atoms<C, A> {
+        let start = self.nodes[self.head.unwrap().index()].next.unwrap().index();
+        let end = start + self.atoms_().count();
+        Atoms {
+            iter: self.nodes[start..end].iter(),
+        }
+    }
+
+    pub fn atoms_(&self) -> impl Iterator<Item = (A, Span)> + '_ {
         let mut head = self.head;
         std::iter::from_fn(move || {
             head.take().map(|h| {