From 6b93e1c007e966f6d79f21a4febe4881df09e6fc Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Sat, 15 Oct 2022 00:01:37 -0400
Subject: [PATCH] Lifetime issue.

---
 src/parser/nom_context.rs | 56 ++++++++++++++++++++++++++++-----------
 src/parser/text.rs        |  5 +++-
 2 files changed, 45 insertions(+), 16 deletions(-)

diff --git a/src/parser/nom_context.rs b/src/parser/nom_context.rs
index d62a3c4..01900db 100644
--- a/src/parser/nom_context.rs
+++ b/src/parser/nom_context.rs
@@ -1,32 +1,58 @@
+use std::cell::RefCell;
+use std::rc::Rc;
+
 use nom::branch::alt;
 use nom::error::VerboseError;
 use nom::IResult;
+use nom::Parser;
 
-pub struct NomContext {
-    pub fail_matcher: Box<dyn FnMut(&str) -> IResult<&str, &str, VerboseError<&str>>>,
+pub type MatcherInner = Rc<RefCell<dyn FnMut(&str) -> IResult<&str, &str, VerboseError<&str>>>>;
+
+struct MatcherRef(MatcherInner);
+
+impl MatcherRef {
+    pub fn new(func: MatcherInner) -> Self {
+        Self(func)
+    }
+}
+
+// type MatcherRef = Rc<RefCell<dyn FnMut(&str) -> IResult<&str, &str, VerboseError<&str>>>>;
+
+enum ChainBehavior {
+    AndParent(Option<MatcherRef>),
+    IgnoreParent(Option<MatcherRef>),
+}
+
+pub struct NomContext<'a> {
+    pub parent: Option<&'a Self>,
+    fail_matcher: ChainBehavior,
     /// You can't have nested bolds or links in org-mode
     pub can_match_bold: bool,
     pub can_match_link: bool,
 }
 
-impl NomContext {
-    pub fn new(
-        fail_matcher: Box<dyn FnMut(&str) -> IResult<&str, &str, VerboseError<&str>>>,
-    ) -> Self {
+impl<'a> NomContext<'a> {
+    pub fn new(fail_matcher: MatcherInner) -> Self {
         NomContext {
-            fail_matcher,
+            parent: None,
+            fail_matcher: ChainBehavior::IgnoreParent(Some(MatcherRef::new(fail_matcher))),
             can_match_bold: true,
             can_match_link: true,
         }
     }
 
-    pub fn with_additional_fail_matcher<>(&self, other: Box<dyn FnMut(&str) -> IResult<&str, &str, VerboseError<&str>>>) -> NomContext {
-        // let new_matcher = alt((&self.fail_matcher, other));
-        // NomContext {
-        //     fail_matcher: new_matcher,
-        //     can_match_bold: self.can_match_bold,
-        //     can_match_link: self.can_match_link
-        // }
-        todo!()
+    pub fn with_additional_fail_matcher(&self, other: MatcherInner) -> NomContext {
+        NomContext {
+            parent: Some(&self),
+            fail_matcher: ChainBehavior::AndParent(Some(MatcherRef::new(other))),
+            can_match_bold: self.can_match_bold,
+            can_match_link: self.can_match_link,
+        }
+    }
+}
+
+impl Parser<&str, &str, VerboseError<&str>> for MatcherRef {
+    fn parse(&mut self, i: &str) -> IResult<&str, &str, VerboseError<&str>> {
+        (&mut *self.0.borrow_mut())(i)
     }
 }
diff --git a/src/parser/text.rs b/src/parser/text.rs
index 77ec244..a15cccd 100644
--- a/src/parser/text.rs
+++ b/src/parser/text.rs
@@ -1,3 +1,6 @@
+use std::cell::RefCell;
+use std::rc::Rc;
+
 /*
 
 hypothetical link:
@@ -133,7 +136,7 @@ pub fn paragraph_end(input: &str) -> Res<&str, &str> {
 }
 
 pub fn document(input: &str) -> Res<&str, Vec<(Vec<TextElement>, &str)>> {
-    let initial_context = NomContext::new(Box::new(paragraph_end));
+    let initial_context = NomContext::new(Rc::new(RefCell::new(paragraph_end)));
     todo!()
     // many1(parser_with_context!(paragraph)(initial_context))(input)
 }