Align set rule

library/src/layout/align.rs

@@ -1,62 +1,22 @@
-use super::{HorizontalAlign, ParNode};
 use crate::prelude::*;
 
-/// Align content along the layouting axes.
+/// Just an empty shell to scope styles.
 #[derive(Debug, Hash)]
-pub struct AlignNode {
-    /// How to align the content horizontally and vertically.
-    pub aligns: Axes<Option<GenAlign>>,
-    /// The content to be aligned.
-    pub body: Content,
-}
+pub enum AlignNode {}
 
-#[node(Layout)]
+#[node]
 impl AlignNode {
+    /// The alignment.
+    #[property(fold, skip)]
+    pub const ALIGNS: Axes<Option<GenAlign>> =
+        Axes::new(GenAlign::Start, GenAlign::Specific(Align::Top));
+
     fn construct(_: &Vm, args: &mut Args) -> SourceResult<Content> {
+        args.expect("body")
+    }
+
+    fn set(...) {
         let aligns: Axes<Option<GenAlign>> = args.find()?.unwrap_or_default();
-        let body: Content = args.expect("body")?;
-
-        if let Axes { x: Some(x), y: None } = aligns {
-            if !body.has::<dyn Layout>() || body.has::<dyn Inline>() {
-                return Ok(body.styled(ParNode::ALIGN, HorizontalAlign(x)));
-            }
-        }
-
-        Ok(Self { aligns, body }.pack())
-    }
-}
-
-impl Layout for AlignNode {
-    fn layout(
-        &self,
-        vt: &mut Vt,
-        styles: StyleChain,
-        regions: Regions,
-    ) -> SourceResult<Fragment> {
-        // The child only needs to expand along an axis if there's no alignment.
-        let mut pod = regions.clone();
-        pod.expand &= self.aligns.as_ref().map(Option::is_none);
-
-        // Align paragraphs inside the child.
-        let mut map = StyleMap::new();
-        if let Some(align) = self.aligns.x {
-            map.set(ParNode::ALIGN, HorizontalAlign(align));
-        }
-
-        // Layout the child.
-        let mut fragment = self.body.layout(vt, styles.chain(&map), pod)?;
-        for (region, frame) in regions.iter().zip(&mut fragment) {
-            // Align in the target size. The target size depends on whether we
-            // should expand.
-            let target = regions.expand.select(region, frame.size());
-            let aligns = self
-                .aligns
-                .map(|align| align.resolve(styles))
-                .unwrap_or(Axes::new(Align::Left, Align::Top));
-
-            frame.resize(target, aligns);
-        }
-
-        Ok(fragment)
+        styles.set(Self::ALIGNS, aligns);
     }
 }

library/src/layout/flow.rs

@@ -125,7 +125,7 @@ impl<'a> FlowLayouter<'a> {
         par: &ParNode,
         styles: StyleChain,
     ) -> SourceResult<()> {
-        let aligns = Axes::new(styles.get(ParNode::ALIGN), Align::Top);
+        let aligns = styles.get(AlignNode::ALIGNS).resolve(styles);
         let leading = styles.get(ParNode::LEADING);
         let consecutive = self.last_was_par;
         let fragment = par.layout(
@@ -172,17 +172,7 @@ impl<'a> FlowLayouter<'a> {
         }
 
         // How to align the block.
-        let aligns = Axes::new(
-            // For non-expanding paragraphs it is crucial that we align the
-            // whole paragraph as it is itself aligned.
-            styles.get(ParNode::ALIGN),
-            // Vertical align node alignment is respected by the flow.
-            block
-                .to::<AlignNode>()
-                .and_then(|aligned| aligned.aligns.y)
-                .map(|align| align.resolve(styles))
-                .unwrap_or(Align::Top),
-        );
+        let aligns = styles.get(AlignNode::ALIGNS).resolve(styles);
 
         // Layout the block itself.
         let sticky = styles.get(BlockNode::STICKY);

library/src/layout/mod.rs

@@ -412,7 +412,9 @@ impl<'a, 'v, 't> Builder<'a, 'v, 't> {
                 bail!(span, "not allowed here");
             }
             self.interrupt_page(styles)?;
-        } else if map.interruption::<ParNode>().is_some() {
+        } else if map.interruption::<ParNode>().is_some()
+            || map.interruption::<AlignNode>().is_some()
+        {
             self.interrupt_par()?;
         } else if map.interruption::<ListNode>().is_some()
             || map.interruption::<EnumNode>().is_some()

library/src/layout/par.rs

@@ -5,6 +5,7 @@ use xi_unicode::LineBreakIterator;
 use typst::model::Key;
 
 use super::{HNode, RepeatNode, Spacing};
+use crate::layout::AlignNode;
 use crate::prelude::*;
 use crate::text::{
     shape, LinebreakNode, Quoter, Quotes, ShapedText, SmartQuoteNode, SpaceNode, TextNode,
@@ -22,9 +23,6 @@ impl ParNode {
     /// The spacing between lines.
     #[property(resolve)]
     pub const LEADING: Length = Em::new(0.65).into();
-    /// How to align text and inline objects in their line.
-    #[property(resolve)]
-    pub const ALIGN: HorizontalAlign = HorizontalAlign(GenAlign::Start);
     /// Whether to justify text in its line.
     pub const JUSTIFY: bool = false;
     /// How to determine line breaks.
@@ -554,7 +552,7 @@ fn prepare<'a>(
         styles,
         hyphenate: shared_get(styles, &par.0, TextNode::HYPHENATE),
         lang: shared_get(styles, &par.0, TextNode::LANG),
-        align: styles.get(ParNode::ALIGN),
+        align: styles.get(AlignNode::ALIGNS).x.resolve(styles),
         justify: styles.get(ParNode::JUSTIFY),
     })
 }

library/src/layout/place.rs

@@ -1,9 +1,8 @@
-use super::AlignNode;
 use crate::prelude::*;
 
 /// Place content at an absolute position.
 #[derive(Debug, Hash)]
-pub struct PlaceNode(pub Content);
+pub struct PlaceNode(pub Content, bool);
 
 #[node(Layout, Behave)]
 impl PlaceNode {
@@ -12,7 +11,8 @@ impl PlaceNode {
         let dx = args.named("dx")?.unwrap_or_default();
         let dy = args.named("dy")?.unwrap_or_default();
         let body = args.expect::<Content>("body")?;
-        Ok(Self(body.moved(Axes::new(dx, dy)).aligned(aligns)).pack())
+        let out_of_flow = aligns.y.is_some();
+        Ok(Self(body.moved(Axes::new(dx, dy)).aligned(aligns), out_of_flow).pack())
     }
 }
 
@@ -49,7 +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.to::<AlignNode>().map_or(false, |node| node.aligns.y.is_some())
+        self.1
     }
 }
 

library/src/layout/stack.rs

@@ -1,6 +1,6 @@
 use typst::model::StyledNode;
 
-use super::{AlignNode, ParNode, Spacing};
+use super::{AlignNode, Spacing};
 use crate::prelude::*;
 
 /// Arrange content and spacing along an axis.
@@ -180,21 +180,13 @@ impl<'a> StackLayouter<'a> {
 
         // Block-axis alignment of the `AlignNode` is respected
         // by the stack node.
-        let align = block
-            .to::<AlignNode>()
-            .and_then(|node| node.aligns.get(self.axis))
-            .map(|align| align.resolve(styles))
-            .unwrap_or_else(|| {
-                if let Some(styled) = block.to::<StyledNode>() {
-                    let map = &styled.map;
-                    if map.contains(ParNode::ALIGN) {
-                        return StyleChain::new(map).get(ParNode::ALIGN);
-                    }
-                }
-
-                self.dir.start().into()
-            });
+        let aligns = if let Some(styled) = block.to::<StyledNode>() {
+            styles.chain(&styled.map).get(AlignNode::ALIGNS)
+        } else {
+            styles.get(AlignNode::ALIGNS)
+        };
 
+        let align = aligns.get(self.axis).resolve(styles);
         let fragment = block.layout(vt, styles, self.regions)?;
         let len = fragment.len();
         for (i, frame) in fragment.into_iter().enumerate() {

library/src/lib.rs

@@ -208,6 +208,6 @@ fn items() -> LangItems {
         math_atom: |atom| math::AtomNode(atom).pack(),
         math_script: |base, sub, sup| math::ScriptNode { base, sub, sup }.pack(),
         math_frac: |num, denom| math::FracNode { num, denom }.pack(),
-        math_align: |count| math::AlignNode(count).pack(),
+        math_align_point: |count| math::AlignPointNode(count).pack(),
     }
 }

library/src/math/mod.rs

@@ -442,14 +442,14 @@ impl Texify for ScriptNode {
     }
 }
 
-/// A math alignment indicator: `&`, `&&`.
+/// A math alignment point: `&`, `&&`.
 #[derive(Debug, Hash)]
-pub struct AlignNode(pub usize);
+pub struct AlignPointNode(pub usize);
 
 #[node(Texify)]
-impl AlignNode {}
+impl AlignPointNode {}
 
-impl Texify for AlignNode {
+impl Texify for AlignPointNode {
     fn texify(&self, _: &mut Texifier) -> SourceResult<()> {
         Ok(())
     }

library/src/shared/ext.rs

@@ -57,7 +57,7 @@ impl ContentExt for Content {
     }
 
     fn aligned(self, aligns: Axes<Option<GenAlign>>) -> Self {
-        crate::layout::AlignNode { aligns, body: self }.pack()
+        self.styled(crate::layout::AlignNode::ALIGNS, aligns)
     }
 
     fn padded(self, padding: Sides<Rel<Length>>) -> Self {

src/geom/corners.rs

@@ -45,16 +45,13 @@ impl<T> Corners<T> {
         }
     }
 
-    /// Zip two instances into an instance.
-    pub fn zip<F, V, W>(self, other: Corners<V>, mut f: F) -> Corners<W>
-    where
-        F: FnMut(T, V) -> W,
-    {
+    /// Zip two instances into one.
+    pub fn zip<U>(self, other: Corners<U>) -> Corners<(T, U)> {
         Corners {
-            top_left: f(self.top_left, other.top_left),
-            top_right: f(self.top_right, other.top_right),
-            bottom_right: f(self.bottom_right, other.bottom_right),
-            bottom_left: f(self.bottom_left, other.bottom_left),
+            top_left: (self.top_left, other.top_left),
+            top_right: (self.top_right, other.top_right),
+            bottom_right: (self.bottom_right, other.bottom_right),
+            bottom_left: (self.bottom_left, other.bottom_left),
         }
     }
 

src/geom/sides.rs

@@ -45,16 +45,13 @@ impl<T> Sides<T> {
         }
     }
 
-    /// Zip two instances into an instance.
-    pub fn zip<F, V, W>(self, other: Sides<V>, mut f: F) -> Sides<W>
-    where
-        F: FnMut(T, V) -> W,
-    {
+    /// Zip two instances into one.
+    pub fn zip<U>(self, other: Sides<U>) -> Sides<(T, U)> {
         Sides {
-            left: f(self.left, other.left),
-            top: f(self.top, other.top),
-            right: f(self.right, other.right),
-            bottom: f(self.bottom, other.bottom),
+            left: (self.left, other.left),
+            top: (self.top, other.top),
+            right: (self.right, other.right),
+            bottom: (self.bottom, other.bottom),
         }
     }
 

src/model/eval.rs

@@ -429,7 +429,7 @@ impl Eval for ast::MathNode {
             Self::Symbol(v) => (vm.items.symbol)(v.get().clone() + ":op".into()),
             Self::Script(v) => v.eval(vm)?,
             Self::Frac(v) => v.eval(vm)?,
-            Self::Align(v) => v.eval(vm)?,
+            Self::AlignPoint(v) => v.eval(vm)?,
             Self::Group(v) => v.eval(vm)?,
             Self::Expr(v) => {
                 if let ast::Expr::Ident(ident) = v {
@@ -480,11 +480,11 @@ impl Eval for ast::Frac {
     }
 }
 
-impl Eval for ast::Align {
+impl Eval for ast::AlignPoint {
     type Output = Content;
 
     fn eval(&self, vm: &mut Vm) -> SourceResult<Self::Output> {
-        Ok((vm.items.math_align)(self.count()))
+        Ok((vm.items.math_align_point)(self.count()))
     }
 }
 

src/model/library.rs

@@ -74,8 +74,8 @@ pub struct LangItems {
         fn(base: Content, sub: Option<Content>, sup: Option<Content>) -> Content,
     /// A fraction in a formula: `x/2`.
     pub math_frac: fn(num: Content, denom: Content) -> Content,
-    /// An alignment indicator in a formula: `&`, `&&`.
-    pub math_align: fn(count: usize) -> Content,
+    /// An alignment point in a formula: `&`, `&&`.
+    pub math_align_point: fn(count: usize) -> Content,
 }
 
 impl Debug for LangItems {
@@ -107,7 +107,7 @@ impl Hash for LangItems {
         self.math_atom.hash(state);
         self.math_script.hash(state);
         self.math_frac.hash(state);
-        self.math_align.hash(state);
+        self.math_align_point.hash(state);
     }
 }
 

src/model/styles.rs

@@ -913,6 +913,14 @@ where
     }
 }
 
+impl Fold for Axes<Option<GenAlign>> {
+    type Output = Axes<GenAlign>;
+
+    fn fold(self, outer: Self::Output) -> Self::Output {
+        self.zip(outer).map(|(inner, outer)| inner.unwrap_or(outer))
+    }
+}
+
 impl<T> Fold for Sides<T>
 where
     T: Fold,
@@ -920,7 +928,7 @@ where
     type Output = Sides<T::Output>;
 
     fn fold(self, outer: Self::Output) -> Self::Output {
-        self.zip(outer, |inner, outer| inner.fold(outer))
+        self.zip(outer).map(|(inner, outer)| inner.fold(outer))
     }
 }
 
@@ -928,7 +936,7 @@ impl Fold for Sides<Option<Rel<Abs>>> {
     type Output = Sides<Rel<Abs>>;
 
     fn fold(self, outer: Self::Output) -> Self::Output {
-        self.zip(outer, |inner, outer| inner.unwrap_or(outer))
+        self.zip(outer).map(|(inner, outer)| inner.unwrap_or(outer))
     }
 }
 
@@ -936,7 +944,7 @@ impl Fold for Sides<Option<Smart<Rel<Length>>>> {
     type Output = Sides<Smart<Rel<Length>>>;
 
     fn fold(self, outer: Self::Output) -> Self::Output {
-        self.zip(outer, |inner, outer| inner.unwrap_or(outer))
+        self.zip(outer).map(|(inner, outer)| inner.unwrap_or(outer))
     }
 }
 
@@ -947,7 +955,7 @@ where
     type Output = Corners<T::Output>;
 
     fn fold(self, outer: Self::Output) -> Self::Output {
-        self.zip(outer, |inner, outer| inner.fold(outer))
+        self.zip(outer).map(|(inner, outer)| inner.fold(outer))
     }
 }
 
@@ -955,7 +963,7 @@ impl Fold for Corners<Option<Rel<Abs>>> {
     type Output = Corners<Rel<Abs>>;
 
     fn fold(self, outer: Self::Output) -> Self::Output {
-        self.zip(outer, |inner, outer| inner.unwrap_or(outer))
+        self.zip(outer).map(|(inner, outer)| inner.unwrap_or(outer))
     }
 }
 

src/syntax/ast.rs

@@ -453,8 +453,8 @@ pub enum MathNode {
     Script(Script),
     /// A fraction: `x/2`.
     Frac(Frac),
-    /// An alignment indicator: `&`, `&&`.
-    Align(Align),
+    /// An alignment point: `&`, `&&`.
+    AlignPoint(AlignPoint),
     /// Grouped mathematical material.
     Group(Math),
     /// An expression.
@@ -472,7 +472,7 @@ impl AstNode for MathNode {
             SyntaxKind::Symbol(_) => node.cast().map(Self::Symbol),
             SyntaxKind::Script => node.cast().map(Self::Script),
             SyntaxKind::Frac => node.cast().map(Self::Frac),
-            SyntaxKind::Align => node.cast().map(Self::Align),
+            SyntaxKind::AlignPoint => node.cast().map(Self::AlignPoint),
             SyntaxKind::Math => node.cast().map(Self::Group),
             _ => node.cast().map(Self::Expr),
         }
@@ -488,7 +488,7 @@ impl AstNode for MathNode {
             Self::Symbol(v) => v.as_untyped(),
             Self::Script(v) => v.as_untyped(),
             Self::Frac(v) => v.as_untyped(),
-            Self::Align(v) => v.as_untyped(),
+            Self::AlignPoint(v) => v.as_untyped(),
             Self::Group(v) => v.as_untyped(),
             Self::Expr(v) => v.as_untyped(),
         }
@@ -558,11 +558,11 @@ impl Frac {
 }
 
 node! {
-    /// An alignment indicator in a formula: `&`, `&&`.
-    Align
+    /// An alignment point in a formula: `&`, `&&`.
+    AlignPoint
 }
 
-impl Align {
+impl AlignPoint {
     /// The number of ampersands.
     pub fn count(&self) -> usize {
         self.0.children().filter(|n| n.kind() == &SyntaxKind::Amp).count()

src/syntax/highlight.rs

@@ -302,7 +302,7 @@ impl Category {
             SyntaxKind::Atom(_) => None,
             SyntaxKind::Script => None,
             SyntaxKind::Frac => None,
-            SyntaxKind::Align => None,
+            SyntaxKind::AlignPoint => None,
 
             SyntaxKind::Ident(_) => match parent.kind() {
                 SyntaxKind::Markup { .. }

src/syntax/kind.rs

@@ -179,8 +179,8 @@ pub enum SyntaxKind {
     Script,
     /// A fraction in a formula: `x/2`.
     Frac,
-    /// An alignment indicator in a formula: `&`, `&&`.
-    Align,
+    /// An alignment point in a formula: `&`, `&&`.
+    AlignPoint,
 
     /// An identifier: `it`.
     Ident(EcoString),
@@ -408,7 +408,7 @@ impl SyntaxKind {
             Self::Atom(_) => "math atom",
             Self::Script => "script",
             Self::Frac => "fraction",
-            Self::Align => "alignment indicator",
+            Self::AlignPoint => "alignment point",
             Self::Ident(_) => "identifier",
             Self::Bool(_) => "boolean",
             Self::Int(_) => "integer",
@@ -528,7 +528,7 @@ impl Hash for SyntaxKind {
             Self::Atom(c) => c.hash(state),
             Self::Script => {}
             Self::Frac => {}
-            Self::Align => {}
+            Self::AlignPoint => {}
             Self::Ident(v) => v.hash(state),
             Self::Bool(v) => v.hash(state),
             Self::Int(v) => v.hash(state),

src/syntax/parsing.rs

@@ -499,7 +499,7 @@ fn math_group(p: &mut Parser, group: Group) {
 }
 
 fn math_align(p: &mut Parser) {
-    p.perform(SyntaxKind::Align, |p| {
+    p.perform(SyntaxKind::AlignPoint, |p| {
         p.assert(SyntaxKind::Amp);
         while p.eat_if(SyntaxKind::Amp) {}
     })

tests/typ/compiler/construct.typ

@@ -10,9 +10,9 @@
 // Ensure that constructor styles win, but not over outer styles.
 // The outer paragraph should be right-aligned,
 // but the B should be center-aligned.
-#set par(align: center)
-#par(align: right)[
-  A #rect(width: 2cm, fill: conifer, inset: 4pt)[B]
+#set list(label: [>])
+#list(label: [--])[
+  #rect(width: 2cm, fill: conifer, inset: 4pt, list[A])
 ]
 
 ---

tests/typ/layout/par.typ

@@ -2,7 +2,7 @@
 
 ---
 // Test ragged-left.
-#set par(align: right)
+#set align(right)
 To the right! Where the sunlight peeks behind the mountain.
 
 ---
@@ -35,11 +35,3 @@ fn main() {}
 - List
 
 Paragraph
-
----
-// Error: 17-20 must be horizontal
-#set par(align: top)
-
----
-// Error: 17-33 expected alignment, found 2d alignment
-#set par(align: horizon + center)

tests/typ/layout/repeat.typ

@@ -32,7 +32,7 @@ A#repeat(rect(width: 2.5em, height: 1em))B
 // Test single repeat in both directions.
 A#repeat(rect(width: 6em, height: 0.7em))B
 
-#set par(align: center)
+#set align(center)
 A#repeat(rect(width: 6em, height: 0.7em))B
 
 #set text(dir: rtl)

tests/typ/layout/spacing.typ

@@ -19,7 +19,7 @@ Add #h(10pt) #h(10pt) up
 
 ---
 // Test spacing collapsing before spacing.
-#set par(align: right)
+#set align(right)
 A #h(0pt) B #h(0pt) \
 A B \
 A #h(-1fr) B

tests/typ/math/style.typ

@@ -11,5 +11,5 @@
 }
 
 #set page(width: auto)
-#set par(align: center)
+#set align(center)
 #table(columns: 1 + modifiers.len(), ..cells)

tests/typ/text/microtype.typ

@@ -18,6 +18,6 @@
 ---
 // Test that lone punctuation doesn't overhang into the margin.
 #set page(margin: 0pt)
-#set par(align: end)
+#set align(end)
 #set text(dir: rtl)
 :

tests/typ/visualize/line.typ

@@ -22,7 +22,7 @@
 #let star(width, ..args) = box(width: width, height: width)[
   #set text(spacing: 0%)
   #set line(..args)
-  #set par(align: left)
+  #set align(left)
   #line(length: +30%, origin: (09.0%, 02%))
   #line(length: +30%, origin: (38.7%, 02%), angle: -72deg)
   #line(length: +30%, origin: (57.5%, 02%), angle: 252deg)