Introduce `Library`

9 files changed, 115 insertions, 112 deletions

diff --git a/cli/src/main.rs b/cli/src/main.rs
index f7fd5903..3db491bb 100644
--- a/cli/src/main.rs
+++ b/cli/src/main.rs
@@ -19,9 +19,10 @@ use siphasher::sip128::{Hasher128, SipHasher};
 use termcolor::{ColorChoice, StandardStream, WriteColor};
 use typst::diag::{FileError, FileResult, SourceError, StrResult};
 use typst::font::{Font, FontBook, FontInfo, FontVariant};
+use typst::model::Library;
 use typst::syntax::{Source, SourceId};
 use typst::util::{Buffer, PathExt};
-use typst::{Config, World};
+use typst::World;
 use walkdir::WalkDir;
 
 type CodespanResult<T> = Result<T, CodespanError>;
@@ -178,15 +179,8 @@ fn typeset(command: TypesetCommand) -> StrResult<()> {
         PathBuf::new()
     };
 
-    let config = Config {
-        root,
-        scope: typst_library::scope(),
-        styles: typst_library::styles(),
-        items: typst_library::items(),
-    };
-
     // Create the world that serves sources, fonts and files.
-    let mut world = SystemWorld::new(config);
+    let mut world = SystemWorld::new(root);
 
     // Typeset.
     typeset_once(&mut world, &command)?;
@@ -371,7 +365,8 @@ fn fonts(command: FontsCommand) -> StrResult<()> {
 
 /// A world that provides access to the operating system.
 struct SystemWorld {
-    config: Prehashed<Config>,
+    root: PathBuf,
+    library: Prehashed<Library>,
     book: Prehashed<FontBook>,
     fonts: Vec<FontSlot>,
     hashes: RefCell<HashMap<PathBuf, FileResult<PathHash>>>,
@@ -394,12 +389,13 @@ struct PathSlot {
 }
 
 impl SystemWorld {
-    fn new(config: Config) -> Self {
+    fn new(root: PathBuf) -> Self {
         let mut searcher = FontSearcher::new();
         searcher.search_system();
 
         Self {
-            config: Prehashed::new(config),
+            root,
+            library: Prehashed::new(typst_library::new()),
             book: Prehashed::new(searcher.book),
             fonts: searcher.fonts,
             hashes: RefCell::default(),
@@ -410,8 +406,12 @@ impl SystemWorld {
 }
 
 impl World for SystemWorld {
-    fn config(&self) -> &Prehashed<Config> {
-        &self.config
+    fn root(&self) -> &Path {
+        &self.root
+    }
+
+    fn library(&self) -> &Prehashed<Library> {
+        &self.library
     }
 
     fn book(&self) -> &Prehashed<FontBook> {
diff --git a/library/src/lib.rs b/library/src/lib.rs
index e5e60968..7fcad183 100644
--- a/library/src/lib.rs
+++ b/library/src/lib.rs
@@ -10,12 +10,17 @@ pub mod structure;
 pub mod text;
 
 use typst::geom::{Align, Color, Dir, GenAlign};
-use typst::model::{LangItems, Node, NodeId, Scope, StyleMap};
+use typst::model::{LangItems, Library, Node, NodeId, Scope, StyleMap};
 
 use self::layout::LayoutRoot;
 
-/// Construct the standard library scope.
-pub fn scope() -> Scope {
+/// Construct the standard library.
+pub fn new() -> Library {
+    Library { scope: scope(), styles: styles(), items: items() }
+}
+
+/// Construct the standard scope.
+fn scope() -> Scope {
     let mut std = Scope::new();
 
     // Text.
@@ -147,12 +152,12 @@ pub fn scope() -> Scope {
 }
 
 /// Construct the standard style map.
-pub fn styles() -> StyleMap {
+fn styles() -> StyleMap {
     StyleMap::new()
 }
 
 /// Construct the standard lang item mapping.
-pub fn items() -> LangItems {
+fn items() -> LangItems {
     LangItems {
         layout: |content, world, styles| content.layout_root(world, styles),
         em: |styles| styles.get(text::TextNode::SIZE),
diff --git a/src/lib.rs b/src/lib.rs
index 319c13ab..75200144 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -42,14 +42,14 @@ pub mod frame;
 pub mod image;
 pub mod syntax;
 
-use std::path::{Path, PathBuf};
+use std::path::Path;
 
 use comemo::{Prehashed, Track};
 
 use crate::diag::{FileResult, SourceResult};
 use crate::font::{Font, FontBook};
 use crate::frame::Frame;
-use crate::model::{LangItems, Route, Scope, StyleChain, StyleMap};
+use crate::model::{Library, Route, StyleChain};
 use crate::syntax::{Source, SourceId};
 use crate::util::Buffer;
 
@@ -62,24 +62,24 @@ pub fn typeset(
     world: &(dyn World + 'static),
     source: &Source,
 ) -> SourceResult<Vec<Frame>> {
-    // Set up the language items.
-    let config = world.config();
-    crate::model::set_lang_items(config.items);
-
     // Evaluate the source file into a module.
     let route = Route::default();
     let module = model::eval(world.track(), route.track(), source)?;
 
     // Layout the module's contents.
-    let styles = StyleChain::with_root(&config.styles);
-    item!(layout)(&module.content, world.track(), styles)
+    let library = world.library();
+    let styles = StyleChain::with_root(&library.styles);
+    (library.items.layout)(&module.content, world.track(), styles)
 }
 
 /// The environment in which typesetting occurs.
 #[comemo::track]
 pub trait World {
-    /// Access the global configuration.
-    fn config(&self) -> &Prehashed<Config>;
+    /// The compilation root.
+    fn root(&self) -> &Path;
+
+    /// The standard library.
+    fn library(&self) -> &Prehashed<Library>;
 
     /// Metadata about all known fonts.
     fn book(&self) -> &Prehashed<FontBook>;
@@ -96,16 +96,3 @@ pub trait World {
     /// Access a source file by id.
     fn source(&self, id: SourceId) -> &Source;
 }
-
-/// The global configuration for typesetting.
-#[derive(Debug, Clone, Hash)]
-pub struct Config {
-    /// The compilation root, relative to which absolute paths are.
-    pub root: PathBuf,
-    /// The scope containing definitions that are available everywhere.
-    pub scope: Scope,
-    /// The default properties for page size, font selection and so on.
-    pub styles: StyleMap,
-    /// Defines which standard library items fulfill which syntactical roles.
-    pub items: LangItems,
-}
diff --git a/src/model/eval.rs b/src/model/eval.rs
index 7f2cea63..fb1bd121 100644
--- a/src/model/eval.rs
+++ b/src/model/eval.rs
@@ -35,10 +35,13 @@ pub fn eval(
         panic!("Tried to cyclicly evaluate {}", path);
     }
 
+    // Hook up the lang items.
+    let library = world.library();
+    super::set_lang_items(library.items.clone());
+
     // Evaluate the module.
     let route = unsafe { Route::insert(route, id) };
-    let std = &world.config().scope;
-    let scopes = Scopes::new(Some(std));
+    let scopes = Scopes::new(Some(&library.scope));
     let mut vm = Vm::new(world, route.track(), id, scopes);
     let result = source.ast()?.eval(&mut vm);
 
diff --git a/src/model/items.rs b/src/model/library.rs
index 50ea8b60..8433e514 100644
--- a/src/model/items.rs
+++ b/src/model/library.rs
@@ -5,41 +5,26 @@ use std::num::NonZeroUsize;
 use comemo::Tracked;
 use once_cell::sync::OnceCell;
 
-use super::{Content, NodeId, StyleChain};
+use super::{Content, NodeId, Scope, StyleChain, StyleMap};
 use crate::diag::SourceResult;
 use crate::frame::Frame;
 use crate::geom::{Abs, Dir};
 use crate::util::{hash128, EcoString};
 use crate::World;
 
-/// Global storage for lang items.
-#[doc(hidden)]
-pub static LANG_ITEMS: OnceCell<LangItems> = OnceCell::new();
-
-/// Set the lang items. This is a hack :(
-///
-/// Passing the lang items everywhere they are needed (especially the text node
-/// related things) is very painful. By storing them globally, in theory, we
-/// break incremental, but only when different sets of lang items are used in
-/// the same program. For this reason, if this function is called multiple
-/// times, the items must be the same.
-pub(crate) fn set_lang_items(items: LangItems) {
-    if LANG_ITEMS.set(items).is_err() {
-        let first = hash128(LANG_ITEMS.get().unwrap());
-        let second = hash128(&items);
-        assert_eq!(first, second, "set differing lang items");
-    }
-}
-
-/// Access a lang item.
-macro_rules! item {
-    ($name:ident) => {
-        $crate::model::LANG_ITEMS.get().unwrap().$name
-    };
+/// A Typst standard library.
+#[derive(Debug, Clone, Hash)]
+pub struct Library {
+    /// The scope containing definitions that are available everywhere.
+    pub scope: Scope,
+    /// The default properties for page size, font selection and so on.
+    pub styles: StyleMap,
+    /// Defines which standard library items fulfill which syntactical roles.
+    pub items: LangItems,
 }
 
 /// Definition of certain standard library items the language is aware of.
-#[derive(Copy, Clone)]
+#[derive(Clone)]
 pub struct LangItems {
     /// The root layout function.
     pub layout: fn(
@@ -128,3 +113,29 @@ impl Hash for LangItems {
         self.math_align.hash(state);
     }
 }
+
+/// Global storage for lang items.
+#[doc(hidden)]
+pub static LANG_ITEMS: OnceCell<LangItems> = OnceCell::new();
+
+/// Set the lang items. This is a hack :(
+///
+/// Passing the lang items everywhere they are needed (especially the text node
+/// related things) is very painful. By storing them globally, in theory, we
+/// break incremental, but only when different sets of lang items are used in
+/// the same program. For this reason, if this function is called multiple
+/// times, the items must be the same.
+pub(crate) fn set_lang_items(items: LangItems) {
+    if let Err(items) = LANG_ITEMS.set(items) {
+        let first = hash128(LANG_ITEMS.get().unwrap());
+        let second = hash128(&items);
+        assert_eq!(first, second, "set differing lang items");
+    }
+}
+
+/// Access a lang item.
+macro_rules! item {
+    ($name:ident) => {
+        $crate::model::LANG_ITEMS.get().unwrap().$name
+    };
+}
diff --git a/src/model/mod.rs b/src/model/mod.rs
index 0f946a40..93e33d5c 100644
--- a/src/model/mod.rs
+++ b/src/model/mod.rs
@@ -1,7 +1,7 @@
 //! Document and computation model.
 
 #[macro_use]
-mod items;
+mod library;
 #[macro_use]
 mod cast;
 #[macro_use]
@@ -34,7 +34,7 @@ pub use self::content::*;
 pub use self::dict::*;
 pub use self::eval::*;
 pub use self::func::*;
-pub use self::items::*;
+pub use self::library::*;
 pub use self::scope::*;
 pub use self::str::*;
 pub use self::styles::*;
diff --git a/src/model/vm.rs b/src/model/vm.rs
index 28885f29..d13be29c 100644
--- a/src/model/vm.rs
+++ b/src/model/vm.rs
@@ -38,7 +38,7 @@ impl<'a> Vm<'a> {
             location,
             scopes,
             flow: None,
-            items: world.config().items,
+            items: world.library().items.clone(),
         }
     }
 
@@ -47,7 +47,7 @@ impl<'a> Vm<'a> {
     pub fn locate(&self, path: &str) -> StrResult<PathBuf> {
         if !self.location.is_detached() {
             if let Some(path) = path.strip_prefix('/') {
-                return Ok(self.world.config().root.join(path).normalize());
+                return Ok(self.world.root().join(path).normalize());
             }
 
             if let Some(dir) = self.world.source(self.location).path().parent() {
diff --git a/tests/src/benches.rs b/tests/src/benches.rs
index 29117a90..1e5550c5 100644
--- a/tests/src/benches.rs
+++ b/tests/src/benches.rs
@@ -1,12 +1,13 @@
-use std::path::{Path, PathBuf};
+use std::path::Path;
 
 use comemo::{Prehashed, Track, Tracked};
 use iai::{black_box, main, Iai};
 use typst::diag::{FileError, FileResult};
 use typst::font::{Font, FontBook};
+use typst::model::Library;
 use typst::syntax::{Source, SourceId, TokenMode, Tokens};
 use typst::util::Buffer;
-use typst::{Config, World};
+use typst::World;
 use unscanny::Scanner;
 
 const TEXT: &str = include_str!("../typ/benches/bench.typ");
@@ -90,7 +91,7 @@ fn bench_render(iai: &mut Iai) {
 }
 
 struct BenchWorld {
-    config: Prehashed<Config>,
+    library: Prehashed<Library>,
     book: Prehashed<FontBook>,
     font: Font,
     source: Source,
@@ -98,22 +99,14 @@ struct BenchWorld {
 
 impl BenchWorld {
     fn new() -> Self {
-        let config = Config {
-            root: PathBuf::new(),
-            scope: typst_library::scope(),
-            styles: typst_library::styles(),
-            items: typst_library::items(),
-        };
-
         let font = Font::new(FONT.into(), 0).unwrap();
         let book = FontBook::from_fonts([&font]);
-        let source = Source::detached(TEXT);
 
         Self {
-            config: Prehashed::new(config),
+            library: Prehashed::new(typst_library::new()),
             book: Prehashed::new(book),
             font,
-            source,
+            source: Source::detached(TEXT),
         }
     }
 
@@ -123,8 +116,12 @@ impl BenchWorld {
 }
 
 impl World for BenchWorld {
-    fn config(&self) -> &Prehashed<Config> {
-        &self.config
+    fn root(&self) -> &Path {
+        Path::new("")
+    }
+
+    fn library(&self) -> &Prehashed<Library> {
+        &self.library
     }
 
     fn book(&self) -> &Prehashed<FontBook> {
diff --git a/tests/src/tests.rs b/tests/src/tests.rs
index 89c83857..2c0a1e71 100644
--- a/tests/src/tests.rs
+++ b/tests/src/tests.rs
@@ -15,10 +15,10 @@ use typst::diag::{bail, FileError, FileResult};
 use typst::font::{Font, FontBook};
 use typst::frame::{Element, Frame};
 use typst::geom::{Abs, RgbaColor, Sides};
-use typst::model::{Smart, Value};
+use typst::model::{Library, Smart, Value};
 use typst::syntax::{Source, SourceId, SyntaxNode};
 use typst::util::{Buffer, PathExt};
-use typst::{Config, World};
+use typst::World;
 use typst_library::layout::PageNode;
 use typst_library::text::{TextNode, TextSize};
 use unscanny::Scanner;
@@ -144,21 +144,22 @@ impl Args {
     }
 }
 
-fn config() -> Config {
+fn library() -> Library {
+    let mut lib = typst_library::new();
+
     // Set page width to 120pt with 10pt margins, so that the inner page is
     // exactly 100pt wide. Page height is unbounded and font size is 10pt so
     // that it multiplies to nice round numbers.
-    let mut styles = typst_library::styles();
-    styles.set(PageNode::WIDTH, Smart::Custom(Abs::pt(120.0).into()));
-    styles.set(PageNode::HEIGHT, Smart::Auto);
-    styles.set(PageNode::MARGIN, Sides::splat(Some(Smart::Custom(Abs::pt(10.0).into()))));
-    styles.set(TextNode::SIZE, TextSize(Abs::pt(10.0).into()));
+    lib.styles.set(PageNode::WIDTH, Smart::Custom(Abs::pt(120.0).into()));
+    lib.styles.set(PageNode::HEIGHT, Smart::Auto);
+    lib.styles
+        .set(PageNode::MARGIN, Sides::splat(Some(Smart::Custom(Abs::pt(10.0).into()))));
+    lib.styles.set(TextNode::SIZE, TextSize(Abs::pt(10.0).into()));
 
     // Hook up helpers into the global scope.
-    let mut scope = typst_library::scope();
-    scope.define("conifer", RgbaColor::new(0x9f, 0xEB, 0x52, 0xFF));
-    scope.define("forest", RgbaColor::new(0x43, 0xA1, 0x27, 0xFF));
-    scope.def_fn("test", move |_, args| {
+    lib.scope.define("conifer", RgbaColor::new(0x9f, 0xEB, 0x52, 0xFF));
+    lib.scope.define("forest", RgbaColor::new(0x43, 0xA1, 0x27, 0xFF));
+    lib.scope.def_fn("test", move |_, args| {
         let lhs = args.expect::<Value>("left-hand side")?;
         let rhs = args.expect::<Value>("right-hand side")?;
         if lhs != rhs {
@@ -166,7 +167,7 @@ fn config() -> Config {
         }
         Ok(Value::None)
     });
-    scope.def_fn("print", move |_, args| {
+    lib.scope.def_fn("print", move |_, args| {
         print!("> ");
         for (i, value) in args.all::<Value>()?.into_iter().enumerate() {
             if i > 0 {
@@ -178,18 +179,13 @@ fn config() -> Config {
         Ok(Value::None)
     });
 
-    Config {
-        root: PathBuf::new(),
-        scope,
-        styles,
-        items: typst_library::items(),
-    }
+    lib
 }
 
 /// A world that provides access to the tests environment.
 struct TestWorld {
     print: PrintConfig,
-    config: Prehashed<Config>,
+    library: Prehashed<Library>,
     book: Prehashed<FontBook>,
     fonts: Vec<Font>,
     paths: RefCell<HashMap<PathBuf, PathSlot>>,
@@ -219,7 +215,7 @@ impl TestWorld {
 
         Self {
             print,
-            config: Prehashed::new(config()),
+            library: Prehashed::new(library()),
             book: Prehashed::new(FontBook::from_fonts(&fonts)),
             fonts,
             paths: RefCell::default(),
@@ -229,8 +225,12 @@ impl TestWorld {
 }
 
 impl World for TestWorld {
-    fn config(&self) -> &Prehashed<Config> {
-        &self.config
+    fn root(&self) -> &Path {
+        Path::new("")
+    }
+
+    fn library(&self) -> &Prehashed<Library> {
+        &self.library
     }
 
     fn book(&self) -> &Prehashed<FontBook> {