Reorganize content type

11 files changed, 42 insertions, 47 deletions

diff --git a/library/src/core/behave.rs b/library/src/core/behave.rs
index 8558faca..ec8fade9 100644
--- a/library/src/core/behave.rs
+++ b/library/src/core/behave.rs
@@ -4,7 +4,7 @@ use typst::model::{capability, Content, StyleChain, StyleVec, StyleVecBuilder};
 
 /// How a node interacts with other nodes.
 #[capability]
-pub trait Behave: 'static + Send + Sync {
+pub trait Behave {
     /// The node's interaction behaviour.
     fn behaviour(&self) -> Behaviour;
 
@@ -62,13 +62,13 @@ impl<'a> BehavedBuilder<'a> {
     /// Push an item into the sequence.
     pub fn push(&mut self, item: Content, styles: StyleChain<'a>) {
         let interaction = item
-            .to::<dyn Behave>()
+            .with::<dyn Behave>()
             .map_or(Behaviour::Supportive, Behave::behaviour);
 
         match interaction {
             Behaviour::Weak(level) => {
                 if matches!(self.last, Behaviour::Weak(_)) {
-                    let item = item.to::<dyn Behave>().unwrap();
+                    let item = item.with::<dyn Behave>().unwrap();
                     let i = self.staged.iter().position(|prev| {
                         let Behaviour::Weak(prev_level) = prev.1 else { return false };
                         level < prev_level
diff --git a/library/src/layout/flow.rs b/library/src/layout/flow.rs
index b69f4f4e..4508023a 100644
--- a/library/src/layout/flow.rs
+++ b/library/src/layout/flow.rs
@@ -25,7 +25,7 @@ impl LayoutBlock for FlowNode {
 
         for (child, map) in self.0.iter() {
             let styles = map.chain(&styles);
-            if let Some(&node) = child.downcast::<VNode>() {
+            if let Some(&node) = child.to::<VNode>() {
                 layouter.layout_spacing(node.amount, styles);
             } else if child.has::<dyn LayoutBlock>() {
                 layouter.layout_block(world, child, styles)?;
@@ -134,7 +134,7 @@ impl FlowLayouter {
 
         // Placed nodes that are out of flow produce placed items which aren't
         // aligned later.
-        if let Some(placed) = block.downcast::<PlaceNode>() {
+        if let Some(placed) = block.to::<PlaceNode>() {
             if placed.out_of_flow() {
                 let frame = block.layout_block(world, &self.regions, styles)?.remove(0);
                 self.items.push(FlowItem::Placed(frame));
@@ -149,7 +149,7 @@ impl FlowLayouter {
             styles.get(ParNode::ALIGN),
             // Vertical align node alignment is respected by the flow.
             block
-                .downcast::<AlignNode>()
+                .to::<AlignNode>()
                 .and_then(|aligned| aligned.aligns.y)
                 .map(|align| align.resolve(styles))
                 .unwrap_or(Align::Top),
diff --git a/library/src/layout/mod.rs b/library/src/layout/mod.rs
index 7b11177b..b05da901 100644
--- a/library/src/layout/mod.rs
+++ b/library/src/layout/mod.rs
@@ -32,8 +32,7 @@ use typst::diag::SourceResult;
 use typst::frame::Frame;
 use typst::geom::*;
 use typst::model::{
-    capability, Content, Node, SequenceNode, Style, StyleChain, StyleVecBuilder,
-    StyledNode,
+    capability, Content, SequenceNode, Style, StyleChain, StyleVecBuilder, StyledNode,
 };
 use typst::World;
 
@@ -48,7 +47,7 @@ use crate::text::{
 
 /// Root-level layout.
 #[capability]
-pub trait LayoutRoot: 'static + Sync + Send {
+pub trait LayoutRoot {
     /// Layout into one frame per page.
     fn layout_root(&self, world: Tracked<dyn World>) -> SourceResult<Vec<Frame>>;
 }
@@ -69,7 +68,7 @@ impl LayoutRoot for Content {
 
 /// Block-level layout.
 #[capability]
-pub trait LayoutBlock: 'static + Sync + Send {
+pub trait LayoutBlock {
     /// Layout into one frame per region.
     fn layout_block(
         &self,
@@ -88,7 +87,7 @@ impl LayoutBlock for Content {
         styles: StyleChain,
     ) -> SourceResult<Vec<Frame>> {
         if !styles.applicable(self) {
-            if let Some(node) = self.to::<dyn LayoutBlock>() {
+            if let Some(node) = self.with::<dyn LayoutBlock>() {
                 let barrier = Style::Barrier(self.id());
                 let styles = barrier.chain(&styles);
                 return node.layout_block(world, regions, styles);
@@ -105,7 +104,7 @@ impl LayoutBlock for Content {
 
 /// Inline-level layout.
 #[capability]
-pub trait LayoutInline: 'static + Sync + Send {
+pub trait LayoutInline {
     /// Layout into a single frame.
     fn layout_inline(
         &self,
@@ -127,13 +126,13 @@ impl LayoutInline for Content {
         assert!(regions.last.is_none());
 
         if !styles.applicable(self) {
-            if let Some(node) = self.to::<dyn LayoutInline>() {
+            if let Some(node) = self.with::<dyn LayoutInline>() {
                 let barrier = Style::Barrier(self.id());
                 let styles = barrier.chain(&styles);
                 return node.layout_inline(world, regions, styles);
             }
 
-            if let Some(node) = self.to::<dyn LayoutBlock>() {
+            if let Some(node) = self.with::<dyn LayoutBlock>() {
                 let barrier = Style::Barrier(self.id());
                 let styles = barrier.chain(&styles);
                 return Ok(node.layout_block(world, regions, styles)?.remove(0));
@@ -312,11 +311,11 @@ impl<'a> Builder<'a> {
         content: &'a Content,
         styles: StyleChain<'a>,
     ) -> SourceResult<()> {
-        if let Some(styled) = content.downcast::<StyledNode>() {
+        if let Some(styled) = content.to::<StyledNode>() {
             return self.styled(styled, styles);
         }
 
-        if let Some(seq) = content.downcast::<SequenceNode>() {
+        if let Some(seq) = content.to::<SequenceNode>() {
             return self.sequence(seq, styles);
         }
 
@@ -347,7 +346,7 @@ impl<'a> Builder<'a> {
         }
 
         let keep = content
-            .downcast::<PagebreakNode>()
+            .to::<PagebreakNode>()
             .map_or(false, |pagebreak| !pagebreak.weak);
         self.interrupt(Interruption::Page, styles, keep)?;
 
@@ -457,12 +456,12 @@ struct DocBuilder<'a> {
 
 impl<'a> DocBuilder<'a> {
     fn accept(&mut self, content: &Content, styles: StyleChain<'a>) -> bool {
-        if let Some(pagebreak) = content.downcast::<PagebreakNode>() {
+        if let Some(pagebreak) = content.to::<PagebreakNode>() {
             self.keep_next = !pagebreak.weak;
             return true;
         }
 
-        if let Some(page) = content.downcast::<PageNode>() {
+        if let Some(page) = content.to::<PageNode>() {
             self.pages.push(page.clone(), styles);
             self.keep_next = false;
             return true;
@@ -498,11 +497,11 @@ impl<'a> FlowBuilder<'a> {
         }
 
         if content.has::<dyn LayoutBlock>() {
-            let is_tight_list = if let Some(node) = content.downcast::<ListNode>() {
+            let is_tight_list = if let Some(node) = content.to::<ListNode>() {
                 node.tight
-            } else if let Some(node) = content.downcast::<EnumNode>() {
+            } else if let Some(node) = content.to::<EnumNode>() {
                 node.tight
-            } else if let Some(node) = content.downcast::<DescNode>() {
+            } else if let Some(node) = content.to::<DescNode>() {
                 node.tight
             } else {
                 false
@@ -576,7 +575,7 @@ impl<'a> ListBuilder<'a> {
             return true;
         }
 
-        if let Some(item) = content.downcast::<ListItem>() {
+        if let Some(item) = content.to::<ListItem>() {
             if self
                 .items
                 .items()
diff --git a/library/src/layout/place.rs b/library/src/layout/place.rs
index 42f7ff7d..a4f05a6c 100644
--- a/library/src/layout/place.rs
+++ b/library/src/layout/place.rs
@@ -49,9 +49,7 @@ impl PlaceNode {
     /// origin. Instead of relative to the parent's current flow/cursor
     /// position.
     pub fn out_of_flow(&self) -> bool {
-        self.0
-            .downcast::<AlignNode>()
-            .map_or(false, |node| node.aligns.y.is_some())
+        self.0.to::<AlignNode>().map_or(false, |node| node.aligns.y.is_some())
     }
 }
 
diff --git a/library/src/layout/spacing.rs b/library/src/layout/spacing.rs
index 74bd2f0f..b42f90ef 100644
--- a/library/src/layout/spacing.rs
+++ b/library/src/layout/spacing.rs
@@ -44,7 +44,7 @@ impl Behave for HNode {
     }
 
     fn larger(&self, prev: &Content) -> bool {
-        let Some(prev) = prev.downcast::<Self>() else { return false };
+        let Some(prev) = prev.to::<Self>() else { return false };
         self.amount > prev.amount
     }
 }
@@ -110,7 +110,7 @@ impl Behave for VNode {
     }
 
     fn larger(&self, prev: &Content) -> bool {
-        let Some(prev) = prev.downcast::<Self>() else { return false };
+        let Some(prev) = prev.to::<Self>() else { return false };
         self.amount > prev.amount
     }
 }
diff --git a/library/src/layout/stack.rs b/library/src/layout/stack.rs
index 02129e1f..12a1c384 100644
--- a/library/src/layout/stack.rs
+++ b/library/src/layout/stack.rs
@@ -182,11 +182,11 @@ impl<'a> StackLayouter<'a> {
         // Block-axis alignment of the `AlignNode` is respected
         // by the stack node.
         let align = block
-            .downcast::<AlignNode>()
+            .to::<AlignNode>()
             .and_then(|node| node.aligns.get(self.axis))
             .map(|align| align.resolve(styles))
             .unwrap_or_else(|| {
-                if let Some(styled) = block.downcast::<StyledNode>() {
+                if let Some(styled) = block.to::<StyledNode>() {
                     let map = &styled.map;
                     if map.contains(ParNode::ALIGN) {
                         return StyleChain::with_root(map).get(ParNode::ALIGN);
diff --git a/library/src/lib.rs b/library/src/lib.rs
index ca10837f..41c841f2 100644
--- a/library/src/lib.rs
+++ b/library/src/lib.rs
@@ -161,7 +161,7 @@ pub fn items() -> LangItems {
         linebreak: |justify| text::LinebreakNode { justify }.pack(),
         text: |text| text::TextNode(text).pack(),
         text_id: NodeId::of::<text::TextNode>(),
-        text_str: |content| Some(&content.downcast::<text::TextNode>()?.0),
+        text_str: |content| Some(&content.to::<text::TextNode>()?.0),
         smart_quote: |double| text::SmartQuoteNode { double }.pack(),
         parbreak: || text::ParbreakNode.pack(),
         strong: |body| text::StrongNode(body).pack(),
diff --git a/library/src/math/mod.rs b/library/src/math/mod.rs
index fb53b52d..1ea03d70 100644
--- a/library/src/math/mod.rs
+++ b/library/src/math/mod.rs
@@ -35,7 +35,7 @@ impl Show for MathNode {
         let mut realized = self
             .clone()
             .pack()
-            .guard(RecipeId::Base(NodeId::of::<Self>()))
+            .guarded(RecipeId::Base(NodeId::of::<Self>()))
             .styled_with_map(map);
 
         if self.display {
diff --git a/library/src/math/tex.rs b/library/src/math/tex.rs
index d7c5493b..ffde719b 100644
--- a/library/src/math/tex.rs
+++ b/library/src/math/tex.rs
@@ -10,7 +10,7 @@ use crate::text::{families, variant, LinebreakNode, SpaceNode, TextNode};
 
 /// Turn a math node into TeX math code.
 #[capability]
-pub trait Texify: 'static + Sync + Send {
+pub trait Texify {
     /// Perform the conversion.
     fn texify(&self) -> EcoString;
 }
@@ -25,7 +25,7 @@ impl Texify for Content {
             return r"\\".into();
         }
 
-        if let Some(node) = self.to::<dyn Texify>() {
+        if let Some(node) = self.with::<dyn Texify>() {
             return node.texify();
         }
 
diff --git a/library/src/text/par.rs b/library/src/text/par.rs
index 37d5e396..196878f8 100644
--- a/library/src/text/par.rs
+++ b/library/src/text/par.rs
@@ -420,7 +420,7 @@ fn collect<'a>(
         let segment = if child.is::<SpaceNode>() {
             full.push(' ');
             Segment::Text(1)
-        } else if let Some(node) = child.downcast::<TextNode>() {
+        } else if let Some(node) = child.to::<TextNode>() {
             let prev = full.len();
             if let Some(case) = styles.get(TextNode::CASE) {
                 full.push_str(&case.apply(&node.0));
@@ -428,18 +428,18 @@ fn collect<'a>(
                 full.push_str(&node.0);
             }
             Segment::Text(full.len() - prev)
-        } else if let Some(node) = child.downcast::<LinebreakNode>() {
+        } else if let Some(node) = child.to::<LinebreakNode>() {
             let c = if node.justify { '\u{2028}' } else { '\n' };
             full.push(c);
             Segment::Text(c.len_utf8())
-        } else if let Some(node) = child.downcast::<SmartQuoteNode>() {
+        } else if let Some(node) = child.to::<SmartQuoteNode>() {
             let prev = full.len();
             if styles.get(TextNode::SMART_QUOTES) {
                 let lang = styles.get(TextNode::LANG);
                 let region = styles.get(TextNode::REGION);
                 let quotes = Quotes::from_lang(lang, region);
                 let peeked = iter.peek().and_then(|(child, _)| {
-                    if let Some(node) = child.downcast::<TextNode>() {
+                    if let Some(node) = child.to::<TextNode>() {
                         node.0.chars().next()
                     } else if child.is::<SmartQuoteNode>() {
                         Some('"')
@@ -455,7 +455,7 @@ fn collect<'a>(
                 full.push(if node.double { '"' } else { '\'' });
             }
             Segment::Text(full.len() - prev)
-        } else if let Some(&node) = child.downcast::<HNode>() {
+        } else if let Some(&node) = child.to::<HNode>() {
             full.push(SPACING_REPLACE);
             Segment::Spacing(node.amount)
         } else if child.has::<dyn LayoutInline>() {
@@ -523,7 +523,7 @@ fn prepare<'a>(
                 }
             },
             Segment::Inline(inline) => {
-                if let Some(repeat) = inline.downcast::<RepeatNode>() {
+                if let Some(repeat) = inline.to::<RepeatNode>() {
                     items.push(Item::Repeat(repeat, styles));
                 } else {
                     let size = Size::new(regions.first.x, regions.base.y);
@@ -606,11 +606,11 @@ fn is_compatible(a: Script, b: Script) -> bool {
 
 /// Get a style property, but only if it is the same for all children of the
 /// paragraph.
-fn shared_get<'a, K: Key<'a>>(
+fn shared_get<'a, K: Key>(
     styles: StyleChain<'a>,
     children: &StyleVec<Content>,
     key: K,
-) -> Option<K::Output> {
+) -> Option<K::Output<'a>> {
     children
         .styles()
         .all(|map| !map.contains(key))
diff --git a/library/src/text/shift.rs b/library/src/text/shift.rs
index 32f110c6..e63211c6 100644
--- a/library/src/text/shift.rs
+++ b/library/src/text/shift.rs
@@ -69,13 +69,11 @@ impl<const S: ShiftKind> Show for ShiftNode<S> {
 /// Find and transform the text contained in `content` to the given script kind
 /// if and only if it only consists of `Text`, `Space`, and `Empty` leaf nodes.
 fn search_text(content: &Content, mode: ShiftKind) -> Option<EcoString> {
-    if content.is_empty() {
-        Some(EcoString::new())
-    } else if content.is::<SpaceNode>() {
+    if content.is::<SpaceNode>() {
         Some(' '.into())
-    } else if let Some(text) = content.downcast::<TextNode>() {
+    } else if let Some(text) = content.to::<TextNode>() {
         convert_script(&text.0, mode)
-    } else if let Some(seq) = content.downcast::<SequenceNode>() {
+    } else if let Some(seq) = content.to::<SequenceNode>() {
         let mut full = EcoString::new();
         for item in seq.0.iter() {
             match search_text(item, mode) {