Support recursive show rules

10 files changed, 60 insertions, 5 deletions

diff --git a/src/library/math/mod.rs b/src/library/math/mod.rs
index 7b4998ca..9709c00c 100644
--- a/src/library/math/mod.rs
+++ b/src/library/math/mod.rs
@@ -36,6 +36,10 @@ impl MathNode {
 }
 
 impl Show for MathNode {
+    fn unguard(&self, _: Selector) -> ShowNode {
+        Self { formula: self.formula.clone(), ..*self }.pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! {
             "formula" => Value::Str(self.formula.clone()),
diff --git a/src/library/prelude.rs b/src/library/prelude.rs
index 584b2ab2..99bff51a 100644
--- a/src/library/prelude.rs
+++ b/src/library/prelude.rs
@@ -15,8 +15,8 @@ pub use crate::eval::{
 pub use crate::frame::*;
 pub use crate::geom::*;
 pub use crate::model::{
-    Content, Fold, Key, Layout, LayoutNode, Regions, Resolve, Show, ShowNode, StyleChain,
-    StyleMap, StyleVec,
+    Content, Fold, Key, Layout, LayoutNode, Regions, Resolve, Selector, Show, ShowNode,
+    StyleChain, StyleMap, StyleVec,
 };
 pub use crate::syntax::{Span, Spanned};
 pub use crate::util::{EcoString, OptionExt};
diff --git a/src/library/structure/heading.rs b/src/library/structure/heading.rs
index 4f6c54f3..468757ad 100644
--- a/src/library/structure/heading.rs
+++ b/src/library/structure/heading.rs
@@ -64,6 +64,10 @@ impl HeadingNode {
 }
 
 impl Show for HeadingNode {
+    fn unguard(&self, sel: Selector) -> ShowNode {
+        Self { body: self.body.unguard(sel), ..*self }.pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! {
             "level" => Value::Int(self.level.get() as i64),
diff --git a/src/library/structure/list.rs b/src/library/structure/list.rs
index 4356ffb4..fca7d5ce 100644
--- a/src/library/structure/list.rs
+++ b/src/library/structure/list.rs
@@ -75,6 +75,17 @@ impl<const L: ListKind> ListNode<L> {
 }
 
 impl<const L: ListKind> Show for ListNode<L> {
+    fn unguard(&self, sel: Selector) -> ShowNode {
+        Self {
+            items: self.items.map(|item| ListItem {
+                body: Box::new(item.body.unguard(sel)),
+                ..*item
+            }),
+            ..*self
+        }
+        .pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! {
             "start" => Value::Int(self.start as i64),
@@ -83,7 +94,7 @@ impl<const L: ListKind> Show for ListNode<L> {
             "items" => Value::Array(
                 self.items
                     .items()
-                    .map(|item| Value::Content((*item.body).clone()))
+                    .map(|item| Value::Content(item.body.as_ref().clone()))
                     .collect()
             ),
         }
diff --git a/src/library/structure/table.rs b/src/library/structure/table.rs
index 7b3f2ac5..304a8681 100644
--- a/src/library/structure/table.rs
+++ b/src/library/structure/table.rs
@@ -51,6 +51,15 @@ impl TableNode {
 }
 
 impl Show for TableNode {
+    fn unguard(&self, sel: Selector) -> ShowNode {
+        Self {
+            tracks: self.tracks.clone(),
+            gutter: self.gutter.clone(),
+            cells: self.cells.iter().map(|cell| cell.unguard(sel)).collect(),
+        }
+        .pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! {
             "cells" => Value::Array(
diff --git a/src/library/text/deco.rs b/src/library/text/deco.rs
index 70040f9c..34c70720 100644
--- a/src/library/text/deco.rs
+++ b/src/library/text/deco.rs
@@ -36,11 +36,15 @@ impl<const L: DecoLine> DecoNode<L> {
     pub const EVADE: bool = true;
 
     fn construct(_: &mut Context, args: &mut Args) -> TypResult<Content> {
-        Ok(Content::show(Self(args.expect::<Content>("body")?)))
+        Ok(Content::show(Self(args.expect("body")?)))
     }
 }
 
 impl<const L: DecoLine> Show for DecoNode<L> {
+    fn unguard(&self, sel: Selector) -> ShowNode {
+        Self(self.0.unguard(sel)).pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! { "body" => Value::Content(self.0.clone()) }
     }
diff --git a/src/library/text/link.rs b/src/library/text/link.rs
index 710fbc47..423bcbfb 100644
--- a/src/library/text/link.rs
+++ b/src/library/text/link.rs
@@ -28,6 +28,14 @@ impl LinkNode {
 }
 
 impl Show for LinkNode {
+    fn unguard(&self, sel: Selector) -> ShowNode {
+        Self {
+            url: self.url.clone(),
+            body: self.body.as_ref().map(|body| body.unguard(sel)),
+        }
+        .pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! {
             "url" => Value::Str(self.url.clone()),
diff --git a/src/library/text/mod.rs b/src/library/text/mod.rs
index ecc0c546..df00d87a 100644
--- a/src/library/text/mod.rs
+++ b/src/library/text/mod.rs
@@ -463,6 +463,10 @@ impl StrongNode {
 }
 
 impl Show for StrongNode {
+    fn unguard(&self, sel: Selector) -> ShowNode {
+        Self(self.0.unguard(sel)).pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! { "body" => Value::Content(self.0.clone()) }
     }
@@ -484,6 +488,10 @@ impl EmphNode {
 }
 
 impl Show for EmphNode {
+    fn unguard(&self, sel: Selector) -> ShowNode {
+        Self(self.0.unguard(sel)).pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! { "body" => Value::Content(self.0.clone()) }
     }
diff --git a/src/library/text/par.rs b/src/library/text/par.rs
index 669d07ba..6c274e7e 100644
--- a/src/library/text/par.rs
+++ b/src/library/text/par.rs
@@ -618,7 +618,10 @@ fn shared_get<'a, K: Key<'a>>(
     children: &StyleVec<ParChild>,
     key: K,
 ) -> Option<K::Output> {
-    children.maps().all(|map| !map.contains(key)).then(|| styles.get(key))
+    children
+        .styles()
+        .all(|map| !map.contains(key))
+        .then(|| styles.get(key))
 }
 
 /// Find suitable linebreaks.
diff --git a/src/library/text/raw.rs b/src/library/text/raw.rs
index ee6c6356..c711aa16 100644
--- a/src/library/text/raw.rs
+++ b/src/library/text/raw.rs
@@ -51,6 +51,10 @@ impl RawNode {
 }
 
 impl Show for RawNode {
+    fn unguard(&self, _: Selector) -> ShowNode {
+        Self { text: self.text.clone(), ..*self }.pack()
+    }
+
     fn encode(&self) -> Dict {
         dict! {
             "text" => Value::Str(self.text.clone()),