From a7b403fd742941f6b163f06876aec96729db707f Mon Sep 17 00:00:00 2001
From: Laurenz <laurmaedje@gmail.com>
Date: Wed, 2 Feb 2022 16:02:23 +0100
Subject: Rename `Node` to `Template`

---
 src/eval/class.rs    |  20 +-
 src/eval/mod.rs      |  94 +++++-----
 src/eval/node.rs     | 507 ---------------------------------------------------
 src/eval/ops.rs      |  22 +--
 src/eval/styles.rs   |  32 ++--
 src/eval/template.rs | 506 ++++++++++++++++++++++++++++++++++++++++++++++++++
 src/eval/value.rs    |  34 ++--
 7 files changed, 606 insertions(+), 609 deletions(-)
 delete mode 100644 src/eval/node.rs
 create mode 100644 src/eval/template.rs

(limited to 'src/eval')

diff --git a/src/eval/class.rs b/src/eval/class.rs
index 91a9daef..4307eecb 100644
--- a/src/eval/class.rs
+++ b/src/eval/class.rs
@@ -1,15 +1,15 @@
 use std::fmt::{self, Debug, Formatter, Write};
 
-use super::{Args, EvalContext, Func, Node, StyleMap, Value};
+use super::{Args, EvalContext, Func, StyleMap, Template, Value};
 use crate::diag::TypResult;
 
-/// A class of [nodes](Node).
+/// A class of nodes.
 ///
 /// You can [construct] an instance of a class in Typst code by invoking the
-/// class as a callable. This always produces some node, but not necessarily one
-/// of fixed type. For example, the `text` constructor does not actually create
-/// a [`TextNode`]. Instead it applies styling to whatever node you pass in and
-/// returns it structurally unchanged.
+/// class as a callable. This always produces a template, but not necessarily a
+/// simple inline or block node. For example, the `text` constructor does not
+/// actually create a [`TextNode`]. Instead it applies styling to whatever node
+/// you pass in and returns it structurally unchanged.
 ///
 /// The arguments you can pass to a class constructor fall into two categories:
 /// Data that is inherent to the instance (e.g. the text of a heading) and style
@@ -50,8 +50,8 @@ impl Class {
             construct: |ctx, args| {
                 let mut styles = StyleMap::new();
                 T::set(args, &mut styles)?;
-                let node = T::construct(ctx, args)?;
-                Ok(Value::Node(node.styled_with_map(styles.scoped())))
+                let template = T::construct(ctx, args)?;
+                Ok(Value::Template(template.styled_with_map(styles.scoped())))
             },
             set: T::set,
         }
@@ -65,7 +65,7 @@ impl Class {
     /// Construct an instance of the class.
     ///
     /// This parses both property and data arguments (in this order) and styles
-    /// the node constructed from the data with the style properties.
+    /// the template constructed from the data with the style properties.
     pub fn construct(&self, ctx: &mut EvalContext, args: &mut Args) -> TypResult<Value> {
         (self.construct)(ctx, args)
     }
@@ -104,7 +104,7 @@ pub trait Construct {
     ///
     /// This is passed only the arguments that remain after execution of the
     /// class's set rule.
-    fn construct(ctx: &mut EvalContext, args: &mut Args) -> TypResult<Node>;
+    fn construct(ctx: &mut EvalContext, args: &mut Args) -> TypResult<Template>;
 }
 
 /// Set style properties of a class.
diff --git a/src/eval/mod.rs b/src/eval/mod.rs
index ebbeec3d..fce8bed4 100644
--- a/src/eval/mod.rs
+++ b/src/eval/mod.rs
@@ -11,18 +11,18 @@ mod styles;
 mod capture;
 mod class;
 mod func;
-mod node;
 mod ops;
 mod scope;
+mod template;
 
 pub use array::*;
 pub use capture::*;
 pub use class::*;
 pub use dict::*;
 pub use func::*;
-pub use node::*;
 pub use scope::*;
 pub use styles::*;
+pub use template::*;
 pub use value::*;
 
 use std::cell::RefMut;
@@ -64,13 +64,13 @@ pub struct Module {
     /// The top-level definitions that were bound in this module.
     pub scope: Scope,
     /// The module's layoutable contents.
-    pub node: Node,
+    pub template: Template,
 }
 
 impl Module {
-    /// Convert this module's node into a layout tree.
+    /// Convert this module's template into a layout tree.
     pub fn into_root(self) -> RootNode {
-        self.node.into_root()
+        self.template.into_root()
     }
 }
 
@@ -143,14 +143,14 @@ impl<'a> EvalContext<'a> {
         self.route.push(id);
 
         // Evaluate the module.
-        let node = ast.eval(self).trace(|| Tracepoint::Import, span)?;
+        let template = ast.eval(self).trace(|| Tracepoint::Import, span)?;
 
         // Restore the old context.
         let new_scopes = mem::replace(&mut self.scopes, prev_scopes);
         self.route.pop().unwrap();
 
         // Save the evaluated module.
-        let module = Module { scope: new_scopes.top, node };
+        let module = Module { scope: new_scopes.top, template };
         self.modules.insert(id, module);
 
         Ok(id)
@@ -170,7 +170,7 @@ impl<'a> EvalContext<'a> {
 }
 
 impl Eval for Markup {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, ctx: &mut EvalContext) -> TypResult<Self::Output> {
         eval_markup(ctx, &mut self.nodes())
@@ -181,12 +181,12 @@ impl Eval for Markup {
 fn eval_markup(
     ctx: &mut EvalContext,
     nodes: &mut impl Iterator<Item = MarkupNode>,
-) -> TypResult<Node> {
+) -> TypResult<Template> {
     let mut seq = Vec::with_capacity(nodes.size_hint().1.unwrap_or_default());
     let mut styles = StyleMap::new();
 
     while let Some(node) = nodes.next() {
-        let result = match node {
+        let template = match node {
             MarkupNode::Expr(Expr::Set(set)) => {
                 let class = set.class();
                 let class = class.eval(ctx)?.cast::<Class>().at(class.span())?;
@@ -206,21 +206,21 @@ fn eval_markup(
             _ => node.eval(ctx)?,
         };
 
-        seq.push(Styled::new(result, styles.clone()));
+        seq.push(Styled::new(template, styles.clone()));
     }
 
-    Ok(Node::Sequence(seq))
+    Ok(Template::Sequence(seq))
 }
 
 impl Eval for MarkupNode {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, ctx: &mut EvalContext) -> TypResult<Self::Output> {
         Ok(match self {
-            Self::Space => Node::Space,
-            Self::Linebreak => Node::Linebreak,
-            Self::Parbreak => Node::Parbreak,
-            Self::Text(text) => Node::Text(text.clone()),
+            Self::Space => Template::Space,
+            Self::Linebreak => Template::Linebreak,
+            Self::Parbreak => Template::Parbreak,
+            Self::Text(text) => Template::Text(text.clone()),
             Self::Strong(strong) => strong.eval(ctx)?,
             Self::Emph(emph) => emph.eval(ctx)?,
             Self::Raw(raw) => raw.eval(ctx)?,
@@ -234,7 +234,7 @@ impl Eval for MarkupNode {
 }
 
 impl Eval for StrongNode {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, ctx: &mut EvalContext) -> TypResult<Self::Output> {
         Ok(self.body().eval(ctx)?.styled(TextNode::STRONG, true))
@@ -242,7 +242,7 @@ impl Eval for StrongNode {
 }
 
 impl Eval for EmphNode {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, ctx: &mut EvalContext) -> TypResult<Self::Output> {
         Ok(self.body().eval(ctx)?.styled(TextNode::EMPH, true))
@@ -250,12 +250,12 @@ impl Eval for EmphNode {
 }
 
 impl Eval for RawNode {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, _: &mut EvalContext) -> TypResult<Self::Output> {
         let code = self.highlighted();
         Ok(if self.block {
-            Node::Block(code.into_block())
+            Template::Block(code.into_block())
         } else {
             code
         })
@@ -263,9 +263,9 @@ impl Eval for RawNode {
 }
 
 impl RawNode {
-    /// Styled node for a code block, with optional syntax highlighting.
-    pub fn highlighted(&self) -> Node {
-        let mut sequence: Vec<Styled<Node>> = vec![];
+    /// Styled template for a code block, with optional syntax highlighting.
+    pub fn highlighted(&self) -> Template {
+        let mut seq: Vec<Styled<Template>> = vec![];
 
         let syntax = if let Some(syntax) = self
             .lang
@@ -279,7 +279,7 @@ impl RawNode {
         ) {
             None
         } else {
-            return Node::Text(self.text.clone()).monospaced();
+            return Template::Text(self.text.clone()).monospaced();
         };
 
         let foreground = THEME
@@ -294,11 +294,11 @@ impl RawNode {
                 let mut highlighter = HighlightLines::new(syntax, &THEME);
                 for (i, line) in self.text.lines().enumerate() {
                     if i != 0 {
-                        sequence.push(Styled::bare(Node::Linebreak));
+                        seq.push(Styled::bare(Template::Linebreak));
                     }
 
                     for (style, piece) in highlighter.highlight(line, &SYNTAXES) {
-                        sequence.push(style_piece(piece, foreground, style));
+                        seq.push(style_piece(piece, foreground, style));
                     }
                 }
             }
@@ -311,23 +311,21 @@ impl RawNode {
                     red.as_ref(),
                     &highlighter,
                     &mut |range, style| {
-                        sequence.push(style_piece(&self.text[range], foreground, style));
+                        seq.push(style_piece(&self.text[range], foreground, style));
                     },
                 )
             }
         }
 
-        Node::Sequence(sequence).monospaced()
+        Template::Sequence(seq).monospaced()
     }
 }
 
 /// Style a piece of text with a syntect style.
-fn style_piece(piece: &str, foreground: Paint, style: SynStyle) -> Styled<Node> {
-    let paint = style.foreground.into();
-    let node = Node::Text(piece.into());
-
+fn style_piece(piece: &str, foreground: Paint, style: SynStyle) -> Styled<Template> {
     let mut styles = StyleMap::new();
 
+    let paint = style.foreground.into();
     if paint != foreground {
         styles.set(TextNode::FILL, paint);
     }
@@ -344,16 +342,16 @@ fn style_piece(piece: &str, foreground: Paint, style: SynStyle) -> Styled<Node>
         styles.set(TextNode::LINES, vec![DecoLine::Underline.into()]);
     }
 
-    Styled::new(node, styles)
+    Styled::new(Template::Text(piece.into()), styles)
 }
 
 impl Eval for MathNode {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, _: &mut EvalContext) -> TypResult<Self::Output> {
-        let text = Node::Text(self.formula.trim().into()).monospaced();
+        let text = Template::Text(self.formula.trim().into()).monospaced();
         Ok(if self.display {
-            Node::Block(text.into_block())
+            Template::Block(text.into_block())
         } else {
             text
         })
@@ -361,10 +359,10 @@ impl Eval for MathNode {
 }
 
 impl Eval for HeadingNode {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, ctx: &mut EvalContext) -> TypResult<Self::Output> {
-        Ok(Node::block(library::HeadingNode {
+        Ok(Template::block(library::HeadingNode {
             child: self.body().eval(ctx)?.into_block(),
             level: self.level(),
         }))
@@ -372,10 +370,10 @@ impl Eval for HeadingNode {
 }
 
 impl Eval for ListNode {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, ctx: &mut EvalContext) -> TypResult<Self::Output> {
-        Ok(Node::block(library::ListNode {
+        Ok(Template::block(library::ListNode {
             child: self.body().eval(ctx)?.into_block(),
             kind: library::Unordered,
         }))
@@ -383,10 +381,10 @@ impl Eval for ListNode {
 }
 
 impl Eval for EnumNode {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, ctx: &mut EvalContext) -> TypResult<Self::Output> {
-        Ok(Node::block(library::ListNode {
+        Ok(Template::block(library::ListNode {
             child: self.body().eval(ctx)?.into_block(),
             kind: library::Ordered(self.number()),
         }))
@@ -402,7 +400,7 @@ impl Eval for Expr {
             Self::Ident(v) => v.eval(ctx),
             Self::Array(v) => v.eval(ctx).map(Value::Array),
             Self::Dict(v) => v.eval(ctx).map(Value::Dict),
-            Self::Template(v) => v.eval(ctx).map(Value::Node),
+            Self::Template(v) => v.eval(ctx).map(Value::Template),
             Self::Group(v) => v.eval(ctx),
             Self::Block(v) => v.eval(ctx),
             Self::Call(v) => v.eval(ctx),
@@ -475,13 +473,13 @@ impl Eval for DictExpr {
 }
 
 impl Eval for TemplateExpr {
-    type Output = Node;
+    type Output = Template;
 
     fn eval(&self, ctx: &mut EvalContext) -> TypResult<Self::Output> {
         ctx.scopes.enter();
-        let node = self.body().eval(ctx)?;
+        let template = self.body().eval(ctx)?;
         ctx.scopes.exit();
-        Ok(node)
+        Ok(template)
     }
 }
 
@@ -899,7 +897,7 @@ impl Eval for IncludeExpr {
         let resolved = path.eval(ctx)?.cast::<EcoString>().at(path.span())?;
         let file = ctx.import(&resolved, path.span())?;
         let module = &ctx.modules[&file];
-        Ok(Value::Node(module.node.clone()))
+        Ok(Value::Template(module.template.clone()))
     }
 }
 
diff --git a/src/eval/node.rs b/src/eval/node.rs
deleted file mode 100644
index e6985faa..00000000
--- a/src/eval/node.rs
+++ /dev/null
@@ -1,507 +0,0 @@
-use std::convert::TryFrom;
-use std::fmt::Debug;
-use std::hash::Hash;
-use std::iter::Sum;
-use std::mem;
-use std::ops::{Add, AddAssign};
-
-use super::{Property, StyleMap, Styled};
-use crate::diag::StrResult;
-use crate::geom::SpecAxis;
-use crate::layout::{Layout, PackedNode, RootNode};
-use crate::library::{
-    FlowChild, FlowNode, PageNode, ParChild, ParNode, PlaceNode, SpacingKind, TextNode,
-};
-use crate::util::EcoString;
-
-/// A partial representation of a layout node.
-///
-/// A node is a composable intermediate representation that can be converted
-/// into a proper layout node by lifting it to a [block-level](PackedNode) or
-/// [root node](RootNode).
-///
-/// When you write `[Hi] + [you]` in Typst, this type's [`Add`] implementation
-/// is invoked. There, multiple nodes are combined into a single
-/// [`Sequence`](Self::Sequence) node.
-#[derive(Debug, PartialEq, Clone, Hash)]
-pub enum Node {
-    /// A word space.
-    Space,
-    /// A line break.
-    Linebreak,
-    /// A paragraph break.
-    Parbreak,
-    /// A column break.
-    Colbreak,
-    /// A page break.
-    Pagebreak,
-    /// Plain text.
-    Text(EcoString),
-    /// Spacing.
-    Spacing(SpecAxis, SpacingKind),
-    /// An inline node.
-    Inline(PackedNode),
-    /// A block node.
-    Block(PackedNode),
-    /// A page node.
-    Page(PageNode),
-    /// Multiple nodes with attached styles.
-    ///
-    /// For example, the Typst template `[Hi *you!*]` would result in the
-    /// sequence:
-    /// - `Text("Hi")` with empty style map,
-    /// - `Space` with empty style map,
-    /// - `Text("you!")` with `TextNode::STRONG` set to `true`.
-    ///
-    /// A sequence may contain nested sequences (meaning this variant
-    /// effectively allows nodes to form trees). All nested sequences can
-    /// equivalently be represented as a single flat sequence, but allowing
-    /// nesting doesn't hurt since we can just recurse into the nested sequences
-    /// during packing. Also, in theory, this allows better complexity when
-    /// adding (large) sequence nodes (just like for a text rope).
-    Sequence(Vec<Styled<Self>>),
-}
-
-impl Node {
-    /// Create an empty node.
-    pub fn new() -> Self {
-        Self::Sequence(vec![])
-    }
-
-    /// Create an inline-level node.
-    pub fn inline<T>(node: T) -> Self
-    where
-        T: Layout + Debug + Hash + Sync + Send + 'static,
-    {
-        Self::Inline(node.pack())
-    }
-
-    /// Create a block-level node.
-    pub fn block<T>(node: T) -> Self
-    where
-        T: Layout + Debug + Hash + Sync + Send + 'static,
-    {
-        Self::Block(node.pack())
-    }
-
-    /// Style this node with a single property.
-    pub fn styled<P: Property>(mut self, key: P, value: P::Value) -> Self {
-        if let Self::Sequence(vec) = &mut self {
-            if let [styled] = vec.as_mut_slice() {
-                styled.map.set(key, value);
-                return self;
-            }
-        }
-
-        self.styled_with_map(StyleMap::with(key, value))
-    }
-
-    /// Style this node with a full style map.
-    pub fn styled_with_map(mut self, styles: StyleMap) -> Self {
-        if styles.is_empty() {
-            return self;
-        }
-
-        if let Self::Sequence(vec) = &mut self {
-            if let [styled] = vec.as_mut_slice() {
-                styled.map.apply(&styles);
-                return self;
-            }
-        }
-
-        Self::Sequence(vec![Styled::new(self, styles)])
-    }
-
-    /// Style this node in monospace.
-    pub fn monospaced(self) -> Self {
-        self.styled(TextNode::MONOSPACE, true)
-    }
-
-    /// Lift to a type-erased block-level node.
-    pub fn into_block(self) -> PackedNode {
-        if let Node::Block(packed) = self {
-            packed
-        } else {
-            let mut packer = Packer::new(false);
-            packer.walk(self, StyleMap::new());
-            packer.into_block()
-        }
-    }
-
-    /// Lift to a root layout tree node.
-    pub fn into_root(self) -> RootNode {
-        let mut packer = Packer::new(true);
-        packer.walk(self, StyleMap::new());
-        packer.into_root()
-    }
-
-    /// Repeat this node `n` times.
-    pub fn repeat(&self, n: i64) -> StrResult<Self> {
-        let count = usize::try_from(n)
-            .map_err(|_| format!("cannot repeat this template {} times", n))?;
-
-        // TODO(style): Make more efficient.
-        Ok(Self::Sequence(vec![Styled::bare(self.clone()); count]))
-    }
-}
-
-impl Default for Node {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
-impl Add for Node {
-    type Output = Self;
-
-    fn add(self, rhs: Self) -> Self::Output {
-        Self::Sequence(match (self, rhs) {
-            (Self::Sequence(mut left), Self::Sequence(right)) => {
-                left.extend(right);
-                left
-            }
-            (Self::Sequence(mut left), right) => {
-                left.push(Styled::bare(right));
-                left
-            }
-            (left, Self::Sequence(mut right)) => {
-                right.insert(0, Styled::bare(left));
-                right
-            }
-            (left, right) => {
-                vec![Styled::bare(left), Styled::bare(right)]
-            }
-        })
-    }
-}
-
-impl AddAssign for Node {
-    fn add_assign(&mut self, rhs: Self) {
-        *self = mem::take(self) + rhs;
-    }
-}
-
-impl Sum for Node {
-    fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {
-        Self::Sequence(iter.map(|n| Styled::bare(n)).collect())
-    }
-}
-
-/// Packs a [`Node`] into a flow or root node.
-struct Packer {
-    /// Whether this packer produces a root node.
-    top: bool,
-    /// The accumulated page nodes.
-    pages: Vec<Styled<PageNode>>,
-    /// The accumulated flow children.
-    flow: Builder<Styled<FlowChild>>,
-    /// The accumulated paragraph children.
-    par: Builder<Styled<ParChild>>,
-}
-
-impl Packer {
-    /// Start a new node-packing session.
-    fn new(top: bool) -> Self {
-        Self {
-            top,
-            pages: vec![],
-            flow: Builder::default(),
-            par: Builder::default(),
-        }
-    }
-
-    /// Finish up and return the resulting flow.
-    fn into_block(mut self) -> PackedNode {
-        self.parbreak(None, false);
-        FlowNode(self.flow.children).pack()
-    }
-
-    /// Finish up and return the resulting root node.
-    fn into_root(mut self) -> RootNode {
-        self.pagebreak();
-        RootNode(self.pages)
-    }
-
-    /// Consider a node with the given styles.
-    fn walk(&mut self, node: Node, styles: StyleMap) {
-        match node {
-            Node::Space => {
-                // A text space is "soft", meaning that it can be eaten up by
-                // adjacent line breaks or explicit spacings.
-                self.par.last.soft(Styled::new(ParChild::text(' '), styles), false);
-            }
-            Node::Linebreak => {
-                // A line break eats up surrounding text spaces.
-                self.par.last.hard();
-                self.push_inline(Styled::new(ParChild::text('\n'), styles));
-                self.par.last.hard();
-            }
-            Node::Parbreak => {
-                // An explicit paragraph break is styled according to the active
-                // styles (`Some(_)`) whereas paragraph breaks forced by
-                // incompatibility take their styles from the preceding
-                // paragraph.
-                self.parbreak(Some(styles), true);
-            }
-            Node::Colbreak => {
-                // Explicit column breaks end the current paragraph and then
-                // discards the paragraph break.
-                self.parbreak(None, false);
-                self.make_flow_compatible(&styles);
-                self.flow.children.push(Styled::new(FlowChild::Skip, styles));
-                self.flow.last.hard();
-            }
-            Node::Pagebreak => {
-                // We must set the flow styles after the page break such that an
-                // empty page created by two page breaks in a row has styles at
-                // all.
-                self.pagebreak();
-                self.flow.styles = styles;
-            }
-            Node::Text(text) => {
-                self.push_inline(Styled::new(ParChild::text(text), styles));
-            }
-            Node::Spacing(SpecAxis::Horizontal, kind) => {
-                // Just like a line break, explicit horizontal spacing eats up
-                // surrounding text spaces.
-                self.par.last.hard();
-                self.push_inline(Styled::new(ParChild::Spacing(kind), styles));
-                self.par.last.hard();
-            }
-            Node::Spacing(SpecAxis::Vertical, kind) => {
-                // Explicit vertical spacing ends the current paragraph and then
-                // discards the paragraph break.
-                self.parbreak(None, false);
-                self.make_flow_compatible(&styles);
-                self.flow.children.push(Styled::new(FlowChild::Spacing(kind), styles));
-                self.flow.last.hard();
-            }
-            Node::Inline(inline) => {
-                self.push_inline(Styled::new(ParChild::Node(inline), styles));
-            }
-            Node::Block(block) => {
-                self.push_block(Styled::new(block, styles));
-            }
-            Node::Page(page) => {
-                if self.top {
-                    self.pagebreak();
-                    self.pages.push(Styled::new(page, styles));
-                } else {
-                    self.push_block(Styled::new(page.0, styles));
-                }
-            }
-            Node::Sequence(list) => {
-                // For a list of nodes, we apply the list's styles to each node
-                // individually.
-                for mut node in list {
-                    node.map.apply(&styles);
-                    self.walk(node.item, node.map);
-                }
-            }
-        }
-    }
-
-    /// Insert an inline-level element into the current paragraph.
-    fn push_inline(&mut self, child: Styled<ParChild>) {
-        // The node must be both compatible with the current page and the
-        // current paragraph.
-        self.make_flow_compatible(&child.map);
-        self.make_par_compatible(&child.map);
-
-        if let Some(styled) = self.par.last.any() {
-            self.push_coalescing(styled);
-        }
-
-        self.push_coalescing(child);
-        self.par.last.any();
-    }
-
-    /// Push a paragraph child, coalescing text nodes with compatible styles.
-    fn push_coalescing(&mut self, child: Styled<ParChild>) {
-        if let ParChild::Text(right) = &child.item {
-            if let Some(Styled { item: ParChild::Text(left), map }) =
-                self.par.children.last_mut()
-            {
-                if child.map.compatible::<TextNode>(map) {
-                    left.0.push_str(&right.0);
-                    return;
-                }
-            }
-        }
-
-        self.par.children.push(child);
-    }
-
-    /// Insert a block-level element into the current flow.
-    fn push_block(&mut self, node: Styled<PackedNode>) {
-        let placed = node.item.is::<PlaceNode>();
-
-        self.parbreak(Some(node.map.clone()), false);
-        self.make_flow_compatible(&node.map);
-        self.flow.children.extend(self.flow.last.any());
-        self.flow.children.push(node.map(FlowChild::Node));
-        self.parbreak(None, false);
-
-        // Prevent paragraph spacing between the placed node and the paragraph
-        // below it.
-        if placed {
-            self.flow.last.hard();
-        }
-    }
-
-    /// Advance to the next paragraph.
-    fn parbreak(&mut self, break_styles: Option<StyleMap>, important: bool) {
-        // Erase any styles that will be inherited anyway.
-        let Builder { mut children, styles, .. } = mem::take(&mut self.par);
-        for Styled { map, .. } in &mut children {
-            map.erase(&styles);
-        }
-
-        // We don't want empty paragraphs.
-        if !children.is_empty() {
-            // The paragraph's children are all compatible with the page, so the
-            // paragraph is too, meaning we don't need to check or intersect
-            // anything here.
-            let par = ParNode(children).pack();
-            self.flow.children.extend(self.flow.last.any());
-            self.flow.children.push(Styled::new(FlowChild::Node(par), styles));
-        }
-
-        // Actually styled breaks have precedence over whatever was before.
-        if break_styles.is_some() {
-            if let Last::Soft(_, false) = self.flow.last {
-                self.flow.last = Last::Any;
-            }
-        }
-
-        // For explicit paragraph breaks, `break_styles` is already `Some(_)`.
-        // For page breaks due to incompatibility, we fall back to the styles
-        // of the preceding thing.
-        let break_styles = break_styles
-            .or_else(|| self.flow.children.last().map(|styled| styled.map.clone()))
-            .unwrap_or_default();
-
-        // Insert paragraph spacing.
-        self.flow
-            .last
-            .soft(Styled::new(FlowChild::Break, break_styles), important);
-    }
-
-    /// Advance to the next page.
-    fn pagebreak(&mut self) {
-        if self.top {
-            self.parbreak(None, false);
-
-            // Take the flow and erase any styles that will be inherited anyway.
-            let Builder { mut children, styles, .. } = mem::take(&mut self.flow);
-            for Styled { map, .. } in &mut children {
-                map.erase(&styles);
-            }
-
-            let flow = FlowNode(children).pack();
-            self.pages.push(Styled::new(PageNode(flow), styles));
-        }
-    }
-
-    /// Break to a new paragraph if the `styles` contain paragraph styles that
-    /// are incompatible with the current paragraph.
-    fn make_par_compatible(&mut self, styles: &StyleMap) {
-        if self.par.children.is_empty() {
-            self.par.styles = styles.clone();
-            return;
-        }
-
-        if !self.par.styles.compatible::<ParNode>(styles) {
-            self.parbreak(Some(styles.clone()), false);
-            self.par.styles = styles.clone();
-            return;
-        }
-
-        self.par.styles.intersect(styles);
-    }
-
-    /// Break to a new page if the `styles` contain page styles that are
-    /// incompatible with the current flow.
-    fn make_flow_compatible(&mut self, styles: &StyleMap) {
-        if self.flow.children.is_empty() && self.par.children.is_empty() {
-            self.flow.styles = styles.clone();
-            return;
-        }
-
-        if self.top && !self.flow.styles.compatible::<PageNode>(styles) {
-            self.pagebreak();
-            self.flow.styles = styles.clone();
-            return;
-        }
-
-        self.flow.styles.intersect(styles);
-    }
-}
-
-/// Container for building a flow or paragraph.
-struct Builder<T> {
-    /// The intersection of the style properties of all `children`.
-    styles: StyleMap,
-    /// The accumulated flow or paragraph children.
-    children: Vec<T>,
-    /// The kind of thing that was last added.
-    last: Last<T>,
-}
-
-impl<T> Default for Builder<T> {
-    fn default() -> Self {
-        Self {
-            styles: StyleMap::new(),
-            children: vec![],
-            last: Last::None,
-        }
-    }
-}
-
-/// The kind of node that was last added to a flow or paragraph. A small finite
-/// state machine used to coalesce spaces.
-///
-/// Soft nodes can only exist when surrounded by `Any` nodes. Not at the
-/// start, end or next to hard nodes. This way, spaces at start and end of
-/// paragraphs and next to `#h(..)` goes away.
-enum Last<N> {
-    /// Start state, nothing there.
-    None,
-    /// Text or a block node or something.
-    Any,
-    /// Hard nodes: Linebreaks and explicit spacing.
-    Hard,
-    /// Soft nodes: Word spaces and paragraph breaks. These are saved here
-    /// temporarily and then applied once an `Any` node appears. The boolean
-    /// says whether this soft node is "important" and preferrable to other soft
-    /// nodes (that is the case for explicit paragraph breaks).
-    Soft(N, bool),
-}
-
-impl<N> Last<N> {
-    /// Transition into the `Any` state and return a soft node to really add
-    /// now if currently in `Soft` state.
-    fn any(&mut self) -> Option<N> {
-        match mem::replace(self, Self::Any) {
-            Self::Soft(soft, _) => Some(soft),
-            _ => None,
-        }
-    }
-
-    /// Transition into the `Soft` state, but only if in `Any`. Otherwise, the
-    /// soft node is discarded.
-    fn soft(&mut self, soft: N, important: bool) {
-        if matches!(
-            (&self, important),
-            (Self::Any, _) | (Self::Soft(_, false), true)
-        ) {
-            *self = Self::Soft(soft, important);
-        }
-    }
-
-    /// Transition into the `Hard` state, discarding a possibly existing soft
-    /// node and preventing further soft nodes from being added.
-    fn hard(&mut self) {
-        *self = Self::Hard;
-    }
-}
diff --git a/src/eval/ops.rs b/src/eval/ops.rs
index 649b8467..b5fa9f9a 100644
--- a/src/eval/ops.rs
+++ b/src/eval/ops.rs
@@ -22,9 +22,9 @@ pub fn join(lhs: Value, rhs: Value) -> StrResult<Value> {
         (Str(a), Str(b)) => Str(a + b),
         (Array(a), Array(b)) => Array(a + b),
         (Dict(a), Dict(b)) => Dict(a + b),
-        (Node(a), Node(b)) => Node(a + b),
-        (Node(a), Str(b)) => Node(a + super::Node::Text(b)),
-        (Str(a), Node(b)) => Node(super::Node::Text(a) + b),
+        (Template(a), Template(b)) => Template(a + b),
+        (Template(a), Str(b)) => Template(a + super::Template::Text(b)),
+        (Str(a), Template(b)) => Template(super::Template::Text(a) + b),
         (a, b) => mismatch!("cannot join {} with {}", a, b),
     })
 }
@@ -85,11 +85,11 @@ pub fn add(lhs: Value, rhs: Value) -> StrResult<Value> {
         (Array(a), Array(b)) => Array(a + b),
         (Dict(a), Dict(b)) => Dict(a + b),
 
-        (Node(a), None) => Node(a),
-        (None, Node(b)) => Node(b),
-        (Node(a), Node(b)) => Node(a + b),
-        (Node(a), Str(b)) => Node(a + super::Node::Text(b)),
-        (Str(a), Node(b)) => Node(super::Node::Text(a) + b),
+        (Template(a), None) => Template(a),
+        (None, Template(b)) => Template(b),
+        (Template(a), Template(b)) => Template(a + b),
+        (Template(a), Str(b)) => Template(a + super::Template::Text(b)),
+        (Str(a), Template(b)) => Template(super::Template::Text(a) + b),
 
         (a, b) => {
             if let (Dyn(a), Dyn(b)) = (&a, &b) {
@@ -178,8 +178,8 @@ pub fn mul(lhs: Value, rhs: Value) -> StrResult<Value> {
         (Int(a), Str(b)) => Str(repeat_str(b, a)?),
         (Array(a), Int(b)) => Array(a.repeat(b)?),
         (Int(a), Array(b)) => Array(b.repeat(a)?),
-        (Node(a), Int(b)) => Node(a.repeat(b)?),
-        (Int(a), Node(b)) => Node(b.repeat(a)?),
+        (Template(a), Int(b)) => Template(a.repeat(b)?),
+        (Int(a), Template(b)) => Template(b.repeat(a)?),
 
         (a, b) => mismatch!("cannot multiply {} with {}", a, b),
     })
@@ -296,7 +296,7 @@ pub fn equal(lhs: &Value, rhs: &Value) -> bool {
         (Str(a), Str(b)) => a == b,
         (Array(a), Array(b)) => a == b,
         (Dict(a), Dict(b)) => a == b,
-        (Node(a), Node(b)) => a == b,
+        (Template(a), Template(b)) => a == b,
         (Func(a), Func(b)) => a == b,
         (Dyn(a), Dyn(b)) => a == b,
 
diff --git a/src/eval/styles.rs b/src/eval/styles.rs
index 5276353a..e3dc51bb 100644
--- a/src/eval/styles.rs
+++ b/src/eval/styles.rs
@@ -144,7 +144,7 @@ impl StyleMap {
     }
 
     /// Whether two style maps are equal when filtered down to properties of the
-    /// node `T`.
+    /// class `T`.
     pub fn compatible<T: 'static>(&self, other: &Self) -> bool {
         let f = |entry: &&Entry| entry.is_of::<T>();
         self.0.iter().filter(f).count() == other.0.iter().filter(f).count()
@@ -242,10 +242,10 @@ impl<'a> StyleChain<'a> {
     /// Barriers interact with [scoped](StyleMap::scoped) styles: A scoped style
     /// can still be read through a single barrier (the one of the node it
     /// _should_ apply to), but a second barrier will make it invisible.
-    pub fn barred<'b>(&'b self, node: TypeId) -> StyleChain<'b> {
-        if self.needs_barrier(node) {
+    pub fn barred<'b>(&'b self, class: TypeId) -> StyleChain<'b> {
+        if self.needs_barrier(class) {
             StyleChain {
-                first: Link::Barrier(node),
+                first: Link::Barrier(class),
                 outer: Some(self),
             }
         } else {
@@ -297,18 +297,18 @@ impl<'a> StyleChain<'a> {
                     .and_then(|entry| entry.downcast::<P>()),
                 depth,
             ),
-            Link::Barrier(node) => (None, depth + (P::node_id() == node) as usize),
+            Link::Barrier(class) => (None, depth + (P::class_id() == class) as usize),
         }
     }
 
-    fn needs_barrier(self, node: TypeId) -> bool {
+    fn needs_barrier(self, class: TypeId) -> bool {
         if let Link::Map(map) = self.first {
-            if map.0.iter().any(|entry| entry.is_of_same(node)) {
+            if map.0.iter().any(|entry| entry.is_of_same(class)) {
                 return true;
             }
         }
 
-        self.outer.map_or(false, |outer| outer.needs_barrier(node))
+        self.outer.map_or(false, |outer| outer.needs_barrier(class))
     }
 }
 
@@ -352,11 +352,11 @@ impl Entry {
     }
 
     fn is_of<T: 'static>(&self) -> bool {
-        self.p.node_id() == TypeId::of::<T>()
+        self.p.class_id() == TypeId::of::<T>()
     }
 
-    fn is_of_same(&self, node: TypeId) -> bool {
-        self.p.node_id() == node
+    fn is_of_same(&self, class: TypeId) -> bool {
+        self.p.class_id() == class
     }
 
     fn downcast<P: Property>(&self) -> Option<&P::Value> {
@@ -402,8 +402,8 @@ pub trait Property: Copy + Sync + Send + 'static {
     /// Whether the property needs folding.
     const FOLDABLE: bool = false;
 
-    /// The type id of the node this property belongs to.
-    fn node_id() -> TypeId;
+    /// The type id of the class this property belongs to.
+    fn class_id() -> TypeId;
 
     /// The default value of the property.
     fn default() -> Self::Value;
@@ -437,7 +437,7 @@ trait Bounds: Sync + Send + 'static {
     fn dyn_fmt(&self, f: &mut Formatter) -> fmt::Result;
     fn dyn_eq(&self, other: &Entry) -> bool;
     fn hash64(&self) -> u64;
-    fn node_id(&self) -> TypeId;
+    fn class_id(&self) -> TypeId;
     fn style_id(&self) -> TypeId;
     fn fold(&self, outer: &Entry) -> Entry;
 }
@@ -467,8 +467,8 @@ impl<P: Property> Bounds for (P, P::Value) {
         state.finish()
     }
 
-    fn node_id(&self) -> TypeId {
-        P::node_id()
+    fn class_id(&self) -> TypeId {
+        P::class_id()
     }
 
     fn style_id(&self) -> TypeId {
diff --git a/src/eval/template.rs b/src/eval/template.rs
new file mode 100644
index 00000000..8a49f84d
--- /dev/null
+++ b/src/eval/template.rs
@@ -0,0 +1,506 @@
+use std::convert::TryFrom;
+use std::fmt::Debug;
+use std::hash::Hash;
+use std::iter::Sum;
+use std::mem;
+use std::ops::{Add, AddAssign};
+
+use super::{Property, StyleMap, Styled};
+use crate::diag::StrResult;
+use crate::geom::SpecAxis;
+use crate::layout::{Layout, PackedNode, RootNode};
+use crate::library::{
+    FlowChild, FlowNode, PageNode, ParChild, ParNode, PlaceNode, SpacingKind, TextNode,
+};
+use crate::util::EcoString;
+
+/// Composable representation of styled content.
+///
+/// This results from:
+/// - anything written between square brackets in Typst
+/// - any class constructor
+///
+/// When you write `[Hi] + [you]` in Typst, this type's [`Add`] implementation
+/// is invoked. There, multiple templates are combined into a single
+/// [`Sequence`](Self::Sequence) template.
+#[derive(Debug, PartialEq, Clone, Hash)]
+pub enum Template {
+    /// A word space.
+    Space,
+    /// A line break.
+    Linebreak,
+    /// A paragraph break.
+    Parbreak,
+    /// A column break.
+    Colbreak,
+    /// A page break.
+    Pagebreak,
+    /// Plain text.
+    Text(EcoString),
+    /// Spacing.
+    Spacing(SpecAxis, SpacingKind),
+    /// An inline node.
+    Inline(PackedNode),
+    /// A block node.
+    Block(PackedNode),
+    /// A page node.
+    Page(PageNode),
+    /// Multiple nodes with attached styles.
+    ///
+    /// For example, the Typst template `[Hi *you!*]` would result in the
+    /// sequence:
+    /// - `Text("Hi")` with empty style map,
+    /// - `Space` with empty style map,
+    /// - `Text("you!")` with `TextNode::STRONG` set to `true`.
+    ///
+    /// A sequence may contain nested sequences (meaning this variant
+    /// effectively allows nodes to form trees). All nested sequences can
+    /// equivalently be represented as a single flat sequence, but allowing
+    /// nesting doesn't hurt since we can just recurse into the nested sequences
+    /// during packing. Also, in theory, this allows better complexity when
+    /// adding (large) sequence nodes (just like for a text rope).
+    Sequence(Vec<Styled<Self>>),
+}
+
+impl Template {
+    /// Create an empty template.
+    pub fn new() -> Self {
+        Self::Sequence(vec![])
+    }
+
+    /// Create a template from an inline-level node.
+    pub fn inline<T>(node: T) -> Self
+    where
+        T: Layout + Debug + Hash + Sync + Send + 'static,
+    {
+        Self::Inline(node.pack())
+    }
+
+    /// Create a template from a block-level node.
+    pub fn block<T>(node: T) -> Self
+    where
+        T: Layout + Debug + Hash + Sync + Send + 'static,
+    {
+        Self::Block(node.pack())
+    }
+
+    /// Style this template with a single property.
+    pub fn styled<P: Property>(mut self, key: P, value: P::Value) -> Self {
+        if let Self::Sequence(vec) = &mut self {
+            if let [styled] = vec.as_mut_slice() {
+                styled.map.set(key, value);
+                return self;
+            }
+        }
+
+        self.styled_with_map(StyleMap::with(key, value))
+    }
+
+    /// Style this template with a full style map.
+    pub fn styled_with_map(mut self, styles: StyleMap) -> Self {
+        if styles.is_empty() {
+            return self;
+        }
+
+        if let Self::Sequence(vec) = &mut self {
+            if let [styled] = vec.as_mut_slice() {
+                styled.map.apply(&styles);
+                return self;
+            }
+        }
+
+        Self::Sequence(vec![Styled::new(self, styles)])
+    }
+
+    /// Style this template in monospace.
+    pub fn monospaced(self) -> Self {
+        self.styled(TextNode::MONOSPACE, true)
+    }
+
+    /// Lift to a type-erased block-level template.
+    pub fn into_block(self) -> PackedNode {
+        if let Template::Block(packed) = self {
+            packed
+        } else {
+            let mut packer = Packer::new(false);
+            packer.walk(self, StyleMap::new());
+            packer.into_block()
+        }
+    }
+
+    /// Lift to a root layout tree node.
+    pub fn into_root(self) -> RootNode {
+        let mut packer = Packer::new(true);
+        packer.walk(self, StyleMap::new());
+        packer.into_root()
+    }
+
+    /// Repeat this template `n` times.
+    pub fn repeat(&self, n: i64) -> StrResult<Self> {
+        let count = usize::try_from(n)
+            .map_err(|_| format!("cannot repeat this template {} times", n))?;
+
+        Ok(Self::Sequence(vec![Styled::bare(self.clone()); count]))
+    }
+}
+
+impl Default for Template {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Add for Template {
+    type Output = Self;
+
+    fn add(self, rhs: Self) -> Self::Output {
+        Self::Sequence(match (self, rhs) {
+            (Self::Sequence(mut left), Self::Sequence(right)) => {
+                left.extend(right);
+                left
+            }
+            (Self::Sequence(mut left), right) => {
+                left.push(Styled::bare(right));
+                left
+            }
+            (left, Self::Sequence(mut right)) => {
+                right.insert(0, Styled::bare(left));
+                right
+            }
+            (left, right) => {
+                vec![Styled::bare(left), Styled::bare(right)]
+            }
+        })
+    }
+}
+
+impl AddAssign for Template {
+    fn add_assign(&mut self, rhs: Self) {
+        *self = mem::take(self) + rhs;
+    }
+}
+
+impl Sum for Template {
+    fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {
+        Self::Sequence(iter.map(|n| Styled::bare(n)).collect())
+    }
+}
+
+/// Packs a [`Template`] into a flow or root node.
+struct Packer {
+    /// Whether this packer produces a root node.
+    top: bool,
+    /// The accumulated page nodes.
+    pages: Vec<Styled<PageNode>>,
+    /// The accumulated flow children.
+    flow: Builder<Styled<FlowChild>>,
+    /// The accumulated paragraph children.
+    par: Builder<Styled<ParChild>>,
+}
+
+impl Packer {
+    /// Start a new template-packing session.
+    fn new(top: bool) -> Self {
+        Self {
+            top,
+            pages: vec![],
+            flow: Builder::default(),
+            par: Builder::default(),
+        }
+    }
+
+    /// Finish up and return the resulting flow.
+    fn into_block(mut self) -> PackedNode {
+        self.parbreak(None, false);
+        FlowNode(self.flow.children).pack()
+    }
+
+    /// Finish up and return the resulting root node.
+    fn into_root(mut self) -> RootNode {
+        self.pagebreak();
+        RootNode(self.pages)
+    }
+
+    /// Consider a template with the given styles.
+    fn walk(&mut self, template: Template, styles: StyleMap) {
+        match template {
+            Template::Space => {
+                // A text space is "soft", meaning that it can be eaten up by
+                // adjacent line breaks or explicit spacings.
+                self.par.last.soft(Styled::new(ParChild::text(' '), styles), false);
+            }
+            Template::Linebreak => {
+                // A line break eats up surrounding text spaces.
+                self.par.last.hard();
+                self.push_inline(Styled::new(ParChild::text('\n'), styles));
+                self.par.last.hard();
+            }
+            Template::Parbreak => {
+                // An explicit paragraph break is styled according to the active
+                // styles (`Some(_)`) whereas paragraph breaks forced by
+                // incompatibility take their styles from the preceding
+                // paragraph.
+                self.parbreak(Some(styles), true);
+            }
+            Template::Colbreak => {
+                // Explicit column breaks end the current paragraph and then
+                // discards the paragraph break.
+                self.parbreak(None, false);
+                self.make_flow_compatible(&styles);
+                self.flow.children.push(Styled::new(FlowChild::Skip, styles));
+                self.flow.last.hard();
+            }
+            Template::Pagebreak => {
+                // We must set the flow styles after the page break such that an
+                // empty page created by two page breaks in a row has styles at
+                // all.
+                self.pagebreak();
+                self.flow.styles = styles;
+            }
+            Template::Text(text) => {
+                self.push_inline(Styled::new(ParChild::text(text), styles));
+            }
+            Template::Spacing(SpecAxis::Horizontal, kind) => {
+                // Just like a line break, explicit horizontal spacing eats up
+                // surrounding text spaces.
+                self.par.last.hard();
+                self.push_inline(Styled::new(ParChild::Spacing(kind), styles));
+                self.par.last.hard();
+            }
+            Template::Spacing(SpecAxis::Vertical, kind) => {
+                // Explicit vertical spacing ends the current paragraph and then
+                // discards the paragraph break.
+                self.parbreak(None, false);
+                self.make_flow_compatible(&styles);
+                self.flow.children.push(Styled::new(FlowChild::Spacing(kind), styles));
+                self.flow.last.hard();
+            }
+            Template::Inline(inline) => {
+                self.push_inline(Styled::new(ParChild::Node(inline), styles));
+            }
+            Template::Block(block) => {
+                self.push_block(Styled::new(block, styles));
+            }
+            Template::Page(page) => {
+                if self.top {
+                    self.pagebreak();
+                    self.pages.push(Styled::new(page, styles));
+                } else {
+                    self.push_block(Styled::new(page.0, styles));
+                }
+            }
+            Template::Sequence(list) => {
+                // For a list of templates, we apply the list's styles to each
+                // templates individually.
+                for Styled { item, mut map } in list {
+                    map.apply(&styles);
+                    self.walk(item, map);
+                }
+            }
+        }
+    }
+
+    /// Insert an inline-level element into the current paragraph.
+    fn push_inline(&mut self, child: Styled<ParChild>) {
+        // The child's map must be both compatible with the current page and the
+        // current paragraph.
+        self.make_flow_compatible(&child.map);
+        self.make_par_compatible(&child.map);
+
+        if let Some(styled) = self.par.last.any() {
+            self.push_coalescing(styled);
+        }
+
+        self.push_coalescing(child);
+        self.par.last.any();
+    }
+
+    /// Push a paragraph child, coalescing text nodes with compatible styles.
+    fn push_coalescing(&mut self, child: Styled<ParChild>) {
+        if let ParChild::Text(right) = &child.item {
+            if let Some(Styled { item: ParChild::Text(left), map }) =
+                self.par.children.last_mut()
+            {
+                if child.map.compatible::<TextNode>(map) {
+                    left.0.push_str(&right.0);
+                    return;
+                }
+            }
+        }
+
+        self.par.children.push(child);
+    }
+
+    /// Insert a block-level element into the current flow.
+    fn push_block(&mut self, node: Styled<PackedNode>) {
+        let placed = node.item.is::<PlaceNode>();
+
+        self.parbreak(Some(node.map.clone()), false);
+        self.make_flow_compatible(&node.map);
+        self.flow.children.extend(self.flow.last.any());
+        self.flow.children.push(node.map(FlowChild::Node));
+        self.parbreak(None, false);
+
+        // Prevent paragraph spacing between the placed node and the paragraph
+        // below it.
+        if placed {
+            self.flow.last.hard();
+        }
+    }
+
+    /// Advance to the next paragraph.
+    fn parbreak(&mut self, break_styles: Option<StyleMap>, important: bool) {
+        // Erase any styles that will be inherited anyway.
+        let Builder { mut children, styles, .. } = mem::take(&mut self.par);
+        for Styled { map, .. } in &mut children {
+            map.erase(&styles);
+        }
+
+        // We don't want empty paragraphs.
+        if !children.is_empty() {
+            // The paragraph's children are all compatible with the page, so the
+            // paragraph is too, meaning we don't need to check or intersect
+            // anything here.
+            let par = ParNode(children).pack();
+            self.flow.children.extend(self.flow.last.any());
+            self.flow.children.push(Styled::new(FlowChild::Node(par), styles));
+        }
+
+        // Actually styled breaks have precedence over whatever was before.
+        if break_styles.is_some() {
+            if let Last::Soft(_, false) = self.flow.last {
+                self.flow.last = Last::Any;
+            }
+        }
+
+        // For explicit paragraph breaks, `break_styles` is already `Some(_)`.
+        // For page breaks due to incompatibility, we fall back to the styles
+        // of the preceding thing.
+        let break_styles = break_styles
+            .or_else(|| self.flow.children.last().map(|styled| styled.map.clone()))
+            .unwrap_or_default();
+
+        // Insert paragraph spacing.
+        self.flow
+            .last
+            .soft(Styled::new(FlowChild::Break, break_styles), important);
+    }
+
+    /// Advance to the next page.
+    fn pagebreak(&mut self) {
+        if self.top {
+            self.parbreak(None, false);
+
+            // Take the flow and erase any styles that will be inherited anyway.
+            let Builder { mut children, styles, .. } = mem::take(&mut self.flow);
+            for Styled { map, .. } in &mut children {
+                map.erase(&styles);
+            }
+
+            let flow = FlowNode(children).pack();
+            self.pages.push(Styled::new(PageNode(flow), styles));
+        }
+    }
+
+    /// Break to a new paragraph if the `styles` contain paragraph styles that
+    /// are incompatible with the current paragraph.
+    fn make_par_compatible(&mut self, styles: &StyleMap) {
+        if self.par.children.is_empty() {
+            self.par.styles = styles.clone();
+            return;
+        }
+
+        if !self.par.styles.compatible::<ParNode>(styles) {
+            self.parbreak(Some(styles.clone()), false);
+            self.par.styles = styles.clone();
+            return;
+        }
+
+        self.par.styles.intersect(styles);
+    }
+
+    /// Break to a new page if the `styles` contain page styles that are
+    /// incompatible with the current flow.
+    fn make_flow_compatible(&mut self, styles: &StyleMap) {
+        if self.flow.children.is_empty() && self.par.children.is_empty() {
+            self.flow.styles = styles.clone();
+            return;
+        }
+
+        if self.top && !self.flow.styles.compatible::<PageNode>(styles) {
+            self.pagebreak();
+            self.flow.styles = styles.clone();
+            return;
+        }
+
+        self.flow.styles.intersect(styles);
+    }
+}
+
+/// Container for building a flow or paragraph.
+struct Builder<T> {
+    /// The intersection of the style properties of all `children`.
+    styles: StyleMap,
+    /// The accumulated flow or paragraph children.
+    children: Vec<T>,
+    /// The kind of thing that was last added.
+    last: Last<T>,
+}
+
+impl<T> Default for Builder<T> {
+    fn default() -> Self {
+        Self {
+            styles: StyleMap::new(),
+            children: vec![],
+            last: Last::None,
+        }
+    }
+}
+
+/// The kind of child that was last added to a flow or paragraph. A small finite
+/// state machine used to coalesce spaces.
+///
+/// Soft children can only exist when surrounded by `Any` children. Not at the
+/// start, end or next to hard children. This way, spaces at start and end of
+/// paragraphs and next to `#h(..)` goes away.
+enum Last<N> {
+    /// Start state, nothing there.
+    None,
+    /// Text or a block node or something.
+    Any,
+    /// Hard children: Linebreaks and explicit spacing.
+    Hard,
+    /// Soft children: Word spaces and paragraph breaks. These are saved here
+    /// temporarily and then applied once an `Any` child appears. The boolean
+    /// says whether this soft child is "important" and preferrable to other soft
+    /// nodes (that is the case for explicit paragraph breaks).
+    Soft(N, bool),
+}
+
+impl<N> Last<N> {
+    /// Transition into the `Any` state and return a soft child to really add
+    /// now if currently in `Soft` state.
+    fn any(&mut self) -> Option<N> {
+        match mem::replace(self, Self::Any) {
+            Self::Soft(soft, _) => Some(soft),
+            _ => None,
+        }
+    }
+
+    /// Transition into the `Soft` state, but only if in `Any`. Otherwise, the
+    /// soft child is discarded.
+    fn soft(&mut self, soft: N, important: bool) {
+        if matches!(
+            (&self, important),
+            (Self::Any, _) | (Self::Soft(_, false), true)
+        ) {
+            *self = Self::Soft(soft, important);
+        }
+    }
+
+    /// Transition into the `Hard` state, discarding a possibly existing soft
+    /// child and preventing further soft nodes from being added.
+    fn hard(&mut self) {
+        *self = Self::Hard;
+    }
+}
diff --git a/src/eval/value.rs b/src/eval/value.rs
index c19794df..d0b822f1 100644
--- a/src/eval/value.rs
+++ b/src/eval/value.rs
@@ -4,7 +4,7 @@ use std::fmt::{self, Debug, Formatter};
 use std::hash::Hash;
 use std::sync::Arc;
 
-use super::{ops, Args, Array, Class, Dict, Func, Node};
+use super::{ops, Args, Array, Class, Dict, Func, Template};
 use crate::diag::StrResult;
 use crate::geom::{Angle, Color, Fractional, Length, Linear, Relative, RgbaColor};
 use crate::layout::Layout;
@@ -42,8 +42,8 @@ pub enum Value {
     Array(Array),
     /// A dictionary value: `(color: #f79143, pattern: dashed)`.
     Dict(Dict),
-    /// A node value: `[*Hi* there]`.
-    Node(Node),
+    /// A template value: `[*Hi* there]`.
+    Template(Template),
     /// An executable function.
     Func(Func),
     /// Captured arguments to a function.
@@ -55,20 +55,20 @@ pub enum Value {
 }
 
 impl Value {
-    /// Create an inline-level node value.
+    /// Create a template value from an inline-level node.
     pub fn inline<T>(node: T) -> Self
     where
         T: Layout + Debug + Hash + Sync + Send + 'static,
     {
-        Self::Node(Node::inline(node))
+        Self::Template(Template::inline(node))
     }
 
-    /// Create a block-level node value.
+    /// Create a template value from a block-level node.
     pub fn block<T>(node: T) -> Self
     where
         T: Layout + Debug + Hash + Sync + Send + 'static,
     {
-        Self::Node(Node::block(node))
+        Self::Template(Template::block(node))
     }
 
     /// The name of the stored value's type.
@@ -88,7 +88,7 @@ impl Value {
             Self::Str(_) => EcoString::TYPE_NAME,
             Self::Array(_) => Array::TYPE_NAME,
             Self::Dict(_) => Dict::TYPE_NAME,
-            Self::Node(_) => Node::TYPE_NAME,
+            Self::Template(_) => Template::TYPE_NAME,
             Self::Func(_) => Func::TYPE_NAME,
             Self::Args(_) => Args::TYPE_NAME,
             Self::Class(_) => Class::TYPE_NAME,
@@ -115,16 +115,16 @@ impl Value {
     }
 
     /// Return the display representation of the value.
-    pub fn show(self) -> Node {
+    pub fn show(self) -> Template {
         match self {
-            Value::None => Node::new(),
-            Value::Int(v) => Node::Text(format_eco!("{}", v)),
-            Value::Float(v) => Node::Text(format_eco!("{}", v)),
-            Value::Str(v) => Node::Text(v),
-            Value::Node(v) => v,
+            Value::None => Template::new(),
+            Value::Int(v) => Template::Text(format_eco!("{}", v)),
+            Value::Float(v) => Template::Text(format_eco!("{}", v)),
+            Value::Str(v) => Template::Text(v),
+            Value::Template(v) => v,
             // For values which can't be shown "naturally", we print the
             // representation in monospace.
-            v => Node::Text(v.repr()).monospaced(),
+            v => Template::Text(v.repr()).monospaced(),
         }
     }
 }
@@ -152,7 +152,7 @@ impl Debug for Value {
             Self::Str(v) => Debug::fmt(v, f),
             Self::Array(v) => Debug::fmt(v, f),
             Self::Dict(v) => Debug::fmt(v, f),
-            Self::Node(_) => f.pad("<template>"),
+            Self::Template(_) => f.pad("<template>"),
             Self::Func(v) => Debug::fmt(v, f),
             Self::Args(v) => Debug::fmt(v, f),
             Self::Class(v) => Debug::fmt(v, f),
@@ -400,7 +400,7 @@ primitive! { Color: "color", Color }
 primitive! { EcoString: "string", Str }
 primitive! { Array: "array", Array }
 primitive! { Dict: "dictionary", Dict }
-primitive! { Node: "template", Node }
+primitive! { Template: "template", Template }
 primitive! { Func: "function", Func, Class(v) => v.constructor() }
 primitive! { Args: "arguments", Args }
 primitive! { Class: "class", Class }
-- 
cgit v1.2.3