[WIP] Label and reference syntax

16 files changed, 129 insertions, 42 deletions

diff --git a/src/eval/mod.rs b/src/eval/mod.rs
index 94d9ef40..7f182f48 100644
--- a/src/eval/mod.rs
+++ b/src/eval/mod.rs
@@ -203,6 +203,8 @@ impl Eval for MarkupNode {
             Self::Heading(heading) => heading.eval(vm)?,
             Self::List(list) => list.eval(vm)?,
             Self::Enum(enum_) => enum_.eval(vm)?,
+            Self::Label(_) => Content::Empty,
+            Self::Ref(label) => Content::show(library::structure::RefNode(label.clone())),
             Self::Expr(expr) => expr.eval(vm)?.display(),
         })
     }
diff --git a/src/library/mod.rs b/src/library/mod.rs
index bd34590a..c1a645fb 100644
--- a/src/library/mod.rs
+++ b/src/library/mod.rs
@@ -37,6 +37,7 @@ pub fn new() -> Scope {
     std.def_fn("smallcaps", text::smallcaps);
 
     // Structure.
+    std.def_node::<structure::RefNode>("ref");
     std.def_node::<structure::HeadingNode>("heading");
     std.def_node::<structure::ListNode>("list");
     std.def_node::<structure::EnumNode>("enum");
diff --git a/src/library/structure/mod.rs b/src/library/structure/mod.rs
index a597211e..088d1e6c 100644
--- a/src/library/structure/mod.rs
+++ b/src/library/structure/mod.rs
@@ -3,9 +3,11 @@
 mod doc;
 mod heading;
 mod list;
+mod reference;
 mod table;
 
 pub use doc::*;
 pub use heading::*;
 pub use list::*;
+pub use reference::*;
 pub use table::*;
diff --git a/src/library/structure/reference.rs b/src/library/structure/reference.rs
new file mode 100644
index 00000000..0eeb4bf5
--- /dev/null
+++ b/src/library/structure/reference.rs
@@ -0,0 +1,28 @@
+use crate::library::prelude::*;
+
+/// A reference to a label.
+#[derive(Debug, Hash)]
+pub struct RefNode(pub EcoString);
+
+#[node(showable)]
+impl RefNode {
+    fn construct(_: &mut Machine, args: &mut Args) -> TypResult<Content> {
+        Ok(Content::show(Self(args.expect("label")?)))
+    }
+}
+
+impl Show for RefNode {
+    fn unguard(&self, _: Selector) -> ShowNode {
+        Self(self.0.clone()).pack()
+    }
+
+    fn encode(&self, _: StyleChain) -> Dict {
+        dict! {
+            "label" => Value::Str(self.0.clone().into()),
+        }
+    }
+
+    fn realize(&self, _: &mut Context, _: StyleChain) -> TypResult<Content> {
+        Ok(Content::Text(format_eco!("@{}", self.0)))
+    }
+}
diff --git a/src/library/text/raw.rs b/src/library/text/raw.rs
index e64636f8..a09d791d 100644
--- a/src/library/text/raw.rs
+++ b/src/library/text/raw.rs
@@ -169,6 +169,9 @@ pub static THEME: Lazy<Theme> = Lazy::new(|| Theme {
         item("markup.raw", Some("#818181"), None),
         item("markup.list", Some("#8b41b1"), None),
         item("comment", Some("#8a8a8a"), None),
+        item("punctuation.shortcut", Some("#1d6c76"), None),
+        item("constant.character.escape", Some("#1d6c76"), None),
+        item("entity.name.label, markup.other.reference", Some("#1d6c76"), None),
         item("keyword, constant.language, variable.language", Some("#d73a49"), None),
         item("storage.type, storage.modifier", Some("#d73a49"), None),
         item("entity.other", Some("#8b41b1"), None),
@@ -177,8 +180,6 @@ pub static THEME: Lazy<Theme> = Lazy::new(|| Theme {
         item("meta.annotation", Some("#301414"), None),
         item("constant", Some("#b60157"), None),
         item("string", Some("#298e0d"), None),
-        item("punctuation.shortcut", Some("#1d6c76"), None),
-        item("constant.character.escape", Some("#1d6c76"), None),
         item("invalid", Some("#ff0000"), None),
     ],
 });
diff --git a/src/parse/mod.rs b/src/parse/mod.rs
index a997421e..0737d4ca 100644
--- a/src/parse/mod.rs
+++ b/src/parse/mod.rs
@@ -175,18 +175,24 @@ fn markup_indented(p: &mut Parser, min_indent: usize) {
         _ => false,
     });
 
+    let marker = p.marker();
     let mut at_start = false;
-    p.perform(NodeKind::Markup { min_indent }, |p| {
-        while !p.eof() {
-            if let Some(NodeKind::Space { newlines: (1 ..) }) = p.peek() {
-                if p.column(p.current_end()) < min_indent {
-                    break;
-                }
-            }
 
-            markup_node(p, &mut at_start);
+    while !p.eof() {
+        match p.peek() {
+            Some(NodeKind::Space { newlines: (1 ..) })
+                if p.column(p.current_end()) < min_indent =>
+            {
+                break;
+            }
+            Some(NodeKind::Label(_)) => break,
+            _ => {}
         }
-    });
+
+        markup_node(p, &mut at_start);
+    }
+
+    marker.end(p, NodeKind::Markup { min_indent });
 }
 
 /// Parse a markup node.
@@ -212,16 +218,18 @@ fn markup_node(p: &mut Parser, at_start: &mut bool) {
 
         // Text and markup.
         NodeKind::Text(_)
+        | NodeKind::Linebreak { .. }
         | NodeKind::NonBreakingSpace
         | NodeKind::Shy
         | NodeKind::EnDash
         | NodeKind::EmDash
         | NodeKind::Ellipsis
         | NodeKind::Quote { .. }
-        | NodeKind::Linebreak { .. }
+        | NodeKind::Escape(_)
         | NodeKind::Raw(_)
         | NodeKind::Math(_)
-        | NodeKind::Escape(_) => {
+        | NodeKind::Label(_)
+        | NodeKind::Ref(_) => {
             p.eat();
         }
 
diff --git a/src/parse/tokens.rs b/src/parse/tokens.rs
index be107f3c..e004dd37 100644
--- a/src/parse/tokens.rs
+++ b/src/parse/tokens.rs
@@ -148,8 +148,10 @@ impl<'s> Tokens<'s> {
             '*' if !self.in_word() => NodeKind::Star,
             '_' if !self.in_word() => NodeKind::Underscore,
             '`' => self.raw(),
-            '$' => self.math(),
             '=' => NodeKind::Eq,
+            '$' => self.math(),
+            '<' => self.label(),
+            '@' => self.reference(),
             c if c == '.' || c.is_ascii_digit() => self.numbering(start, c),
 
             // Plain text.
@@ -277,7 +279,9 @@ impl<'s> Tokens<'s> {
             // Parenthesis and hashtag.
             '[' | ']' | '{' | '}' | '#' |
             // Markup.
-            '~' | '\'' | '"' | '*' | '_' | '`' | '$' | '=' | '-' | '.' => {
+            '~' | '-' | '.' | ':' |
+            '\'' | '"' | '*' | '_' | '`' | '$' | '=' |
+            '<' | '>' | '@' => {
                 self.s.expect(c);
                 NodeKind::Escape(c)
             }
@@ -453,6 +457,29 @@ impl<'s> Tokens<'s> {
         }
     }
 
+    fn label(&mut self) -> NodeKind {
+        let label = self.s.eat_while(is_id_continue);
+        if self.s.eat_if('>') {
+            if !label.is_empty() {
+                NodeKind::Label(label.into())
+            } else {
+                NodeKind::Error(SpanPos::Full, "label cannot be empty".into())
+            }
+        } else {
+            self.terminated = false;
+            NodeKind::Error(SpanPos::End, "expected closing angle bracket".into())
+        }
+    }
+
+    fn reference(&mut self) -> NodeKind {
+        let label = self.s.eat_while(is_id_continue);
+        if !label.is_empty() {
+            NodeKind::Ref(label.into())
+        } else {
+            NodeKind::Error(SpanPos::Full, "label cannot be empty".into())
+        }
+    }
+
     fn ident(&mut self, start: usize) -> NodeKind {
         self.s.eat_while(is_id_continue);
         match self.s.from(start) {
diff --git a/src/syntax/ast.rs b/src/syntax/ast.rs
index 67f9e038..10bee4e8 100644
--- a/src/syntax/ast.rs
+++ b/src/syntax/ast.rs
@@ -84,6 +84,8 @@ impl Markup {
             NodeKind::Heading => node.cast().map(MarkupNode::Heading),
             NodeKind::List => node.cast().map(MarkupNode::List),
             NodeKind::Enum => node.cast().map(MarkupNode::Enum),
+            NodeKind::Label(v) => Some(MarkupNode::Label(v.clone())),
+            NodeKind::Ref(v) => Some(MarkupNode::Ref(v.clone())),
             _ => node.cast().map(MarkupNode::Expr),
         })
     }
@@ -116,6 +118,10 @@ pub enum MarkupNode {
     List(ListNode),
     /// An item in an enumeration (ordered list): `1. ...`.
     Enum(EnumNode),
+    /// A label.
+    Label(EcoString),
+    /// A reference.
+    Ref(EcoString),
     /// An expression.
     Expr(Expr),
 }
diff --git a/src/syntax/highlight.rs b/src/syntax/highlight.rs
index b52234d4..ff02190a 100644
--- a/src/syntax/highlight.rs
+++ b/src/syntax/highlight.rs
@@ -153,6 +153,10 @@ pub enum Category {
     Punctuation,
     /// A line or block comment.
     Comment,
+    /// An easily typable shortcut to a unicode codepoint.
+    Shortcut,
+    /// An escape sequence.
+    Escape,
     /// Strong text.
     Strong,
     /// Emphasized text.
@@ -165,10 +169,10 @@ pub enum Category {
     Heading,
     /// A list or enumeration.
     List,
-    /// An easily typable shortcut to a unicode codepoint.
-    Shortcut,
-    /// An escape sequence.
-    Escape,
+    /// A label.
+    Label,
+    /// A reference.
+    Ref,
     /// A keyword.
     Keyword,
     /// An operator symbol.
@@ -212,6 +216,13 @@ impl Category {
             NodeKind::Dot => Some(Category::Punctuation),
             NodeKind::LineComment => Some(Category::Comment),
             NodeKind::BlockComment => Some(Category::Comment),
+            NodeKind::Linebreak { .. } => Some(Category::Shortcut),
+            NodeKind::NonBreakingSpace => Some(Category::Shortcut),
+            NodeKind::Shy => Some(Category::Shortcut),
+            NodeKind::EnDash => Some(Category::Shortcut),
+            NodeKind::EmDash => Some(Category::Shortcut),
+            NodeKind::Ellipsis => Some(Category::Shortcut),
+            NodeKind::Escape(_) => Some(Category::Escape),
             NodeKind::Strong => Some(Category::Strong),
             NodeKind::Emph => Some(Category::Emph),
             NodeKind::Raw(_) => Some(Category::Raw),
@@ -222,13 +233,8 @@ impl Category {
                 _ => Some(Category::Operator),
             },
             NodeKind::EnumNumbering(_) => Some(Category::List),
-            NodeKind::Linebreak { .. } => Some(Category::Shortcut),
-            NodeKind::NonBreakingSpace => Some(Category::Shortcut),
-            NodeKind::Shy => Some(Category::Shortcut),
-            NodeKind::EnDash => Some(Category::Shortcut),
-            NodeKind::EmDash => Some(Category::Shortcut),
-            NodeKind::Ellipsis => Some(Category::Shortcut),
-            NodeKind::Escape(_) => Some(Category::Escape),
+            NodeKind::Label(_) => Some(Category::Label),
+            NodeKind::Ref(_) => Some(Category::Ref),
             NodeKind::Not => Some(Category::Keyword),
             NodeKind::And => Some(Category::Keyword),
             NodeKind::Or => Some(Category::Keyword),
@@ -344,14 +350,16 @@ impl Category {
             Self::Bracket => "punctuation.definition.typst",
             Self::Punctuation => "punctuation.typst",
             Self::Comment => "comment.typst",
+            Self::Shortcut => "punctuation.shortcut.typst",
+            Self::Escape => "constant.character.escape.content.typst",
             Self::Strong => "markup.bold.typst",
             Self::Emph => "markup.italic.typst",
             Self::Raw => "markup.raw.typst",
             Self::Math => "string.other.math.typst",
             Self::Heading => "markup.heading.typst",
             Self::List => "markup.list.typst",
-            Self::Shortcut => "punctuation.shortcut.typst",
-            Self::Escape => "constant.character.escape.content.typst",
+            Self::Label => "entity.name.label.typst",
+            Self::Ref => "markup.other.reference.typst",
             Self::Keyword => "keyword.typst",
             Self::Operator => "keyword.operator.typst",
             Self::None => "constant.language.none.typst",
diff --git a/src/syntax/mod.rs b/src/syntax/mod.rs
index 4bae7a4b..eb070a04 100644
--- a/src/syntax/mod.rs
+++ b/src/syntax/mod.rs
@@ -723,6 +723,10 @@ pub enum NodeKind {
     ///
     /// Can also exist without the number: `.`.
     EnumNumbering(Option<usize>),
+    /// A label: `<label>`.
+    Label(EcoString),
+    /// A reference: `@label`.
+    Ref(EcoString),
     /// An identifier: `center`.
     Ident(EcoString),
     /// A boolean: `true`, `false`.
@@ -935,6 +939,8 @@ impl NodeKind {
             Self::Heading => "heading",
             Self::Enum => "enumeration item",
             Self::EnumNumbering(_) => "enumeration item numbering",
+            Self::Label(_) => "label",
+            Self::Ref(_) => "reference",
             Self::Ident(_) => "identifier",
             Self::Bool(_) => "boolean",
             Self::Int(_) => "integer",
@@ -1060,6 +1066,8 @@ impl Hash for NodeKind {
             Self::Heading => {}
             Self::Enum => {}
             Self::EnumNumbering(num) => num.hash(state),
+            Self::Label(c) => c.hash(state),
+            Self::Ref(c) => c.hash(state),
             Self::Ident(v) => v.hash(state),
             Self::Bool(v) => v.hash(state),
             Self::Int(v) => v.hash(state),
diff --git a/tests/ref/text/escape.png b/tests/ref/text/escape.png
index 77cc21f2..5ee9dbf8 100644
--- a/tests/ref/text/escape.png
+++ b/tests/ref/text/escape.png
diff --git a/tests/ref/text/raw.png b/tests/ref/text/raw.png
index 2c101dcb..3a7691fd 100644
--- a/tests/ref/text/raw.png
+++ b/tests/ref/text/raw.png
diff --git a/tests/typ/code/import.typ b/tests/typ/code/import.typ
index aef5e9c4..2c27f135 100644
--- a/tests/typ/code/import.typ
+++ b/tests/typ/code/import.typ
@@ -30,7 +30,7 @@
 // Who needs whitespace anyways?
 #import*from"target.typ"
 
-// Should output `Hi`.
+// Should output `bye`.
 // Stop at semicolon.
 #import a, c from "target.typ";bye
 
@@ -93,25 +93,21 @@ This is never reached.
 // Error: 17-18 expected expression, found comma
 #import a, b, c,, from "target.typ"
 
-// Should output `"target.typ"`.
 // Error: 1-6 unexpected keyword `from`
 #from "target.typ"
 
-// Should output `target`.
 // Error: 2:2 expected semicolon or line break
 #import * from "target.typ
 "target
 
-// Should output `@ 0.2.1`.
 // Error: 28 expected semicolon or line break
-#import * from "target.typ" @ 0.2.1
+#import * from "target.typ" § 0.2.1
 
 // A star in the list.
 // Error: 12-13 expected expression, found star
 #import a, *, b from "target.typ"
 
 // An item after a star.
-// Should output `, a from "target.typ"`.
 // Error: 10 expected keyword `from`
 #import *, a from "target.typ"
 
diff --git a/tests/typ/text/escape.typ b/tests/typ/text/escape.typ
index e03d73e5..ccaf78e9 100644
--- a/tests/typ/text/escape.typ
+++ b/tests/typ/text/escape.typ
@@ -3,10 +3,10 @@
 ---
 // Escapable symbols.
 \\ \/ \[ \] \{ \} \# \* \_ \
-\= \~ \` \$ \" \'
+\= \~ \` \$ \" \' \< \> \@
 
 // No need to escape.
-( ) ; < >
+( ) ;
 
 // Unescapable.
 \a \: \; \( \)
diff --git a/tests/typ/text/raw.typ b/tests/typ/text/raw.typ
index cf497d75..c17c8fec 100644
--- a/tests/typ/text/raw.typ
+++ b/tests/typ/text/raw.typ
@@ -31,11 +31,11 @@ Text
 The keyword ```rust let```.
 
 // Trimming depends on number backticks.
-<``> \
-<` untrimmed `> \
-<``` trimmed` ```> \
-<``` trimmed ```> \
-<``` trimmed```>
+(``) \
+(` untrimmed `) \
+(``` trimmed` ```) \
+(``` trimmed ```) \
+(``` trimmed```) \
 
 ---
 // First line is not dedented and leading space is still possible.
diff --git a/tools/support/typst.tmLanguage.json b/tools/support/typst.tmLanguage.json
index 0f8102e6..8e1a66c4 100644
--- a/tools/support/typst.tmLanguage.json
+++ b/tools/support/typst.tmLanguage.json
@@ -81,7 +81,7 @@
           "name": "markup.heading.typst",
           "contentName": "entity.name.section.typst",
           "begin": "^\\s*=+\\s+",
-          "end": "\n",
+          "end": "\n|(?=<)",
           "beginCaptures": { "0": { "name": "punctuation.definition.heading.typst" } },
           "patterns": [{ "include": "#markup" }]
         },