typst/src/lib.rs
2022-10-27 15:56:03 +02:00

143 lines
4.5 KiB
Rust

//! The compiler for the _Typst_ typesetting language.
//!
//! # Steps
//! - **Parsing:** The parsing step first transforms a plain string into an
//! [iterator of tokens][tokens]. This token stream is [parsed] into a [syntax
//! tree]. The tree itself is untyped, but the [AST] module provides a typed
//! layer over it.
//! - **Evaluation:** The next step is to [evaluate] the markup. This produces a
//! [module], consisting of a scope of values that were exported by the code
//! and [content], a hierarchical, styled representation of the text,
//! structure, layouts, etc. of the module. The nodes of the content tree are
//! well structured and order-independent and thus much better suited for
//! layouting than the raw markup.
//! - **Layouting:** Next, the content is [layouted] into a portable version of
//! the typeset document. The output of this is a collection of [`Frame`]s
//! (one per page), ready for exporting.
//! - **Exporting:** The finished layout can be exported into a supported
//! format. Currently, the only supported output format is [PDF].
//!
//! [tokens]: syntax::Tokens
//! [parsed]: syntax::parse
//! [syntax tree]: syntax::SyntaxNode
//! [AST]: syntax::ast
//! [evaluate]: model::eval
//! [module]: model::Module
//! [content]: model::Content
//! [layouted]: model::layout
//! [PDF]: export::pdf
#![allow(clippy::len_without_is_empty)]
#![allow(clippy::or_fun_call)]
#![allow(clippy::try_err)]
#[macro_use]
pub mod util;
#[macro_use]
pub mod geom;
#[macro_use]
pub mod diag;
#[macro_use]
pub mod model;
pub mod export;
pub mod font;
pub mod frame;
pub mod image;
pub mod library;
pub mod syntax;
use std::num::NonZeroUsize;
use std::path::{Path, PathBuf};
use comemo::{Prehashed, Track};
use crate::diag::{FileResult, SourceResult};
use crate::font::{Font, FontBook};
use crate::frame::Frame;
use crate::model::StyleMap;
use crate::model::{Content, Route, Scope};
use crate::syntax::{Source, SourceId};
use crate::util::{Buffer, EcoString};
/// Typeset a source file into a collection of layouted frames.
///
/// Returns either a vector of frames representing individual pages or
/// diagnostics in the form of a vector of error message with file and span
/// information.
pub fn typeset(
world: &(dyn World + 'static),
main: SourceId,
) -> SourceResult<Vec<Frame>> {
let route = Route::default();
let module = model::eval(world.track(), route.track(), main)?;
model::layout(world.track(), &module.content)
}
/// The environment in which typesetting occurs.
#[comemo::track]
pub trait World {
/// Access the global configuration.
fn config(&self) -> &Prehashed<Config>;
/// Metadata about all known fonts.
fn book(&self) -> &Prehashed<FontBook>;
/// Try to access the font with the given id.
fn font(&self, id: usize) -> Option<Font>;
/// Try to access a file at a path.
fn file(&self, path: &Path) -> FileResult<Buffer>;
/// Try to resolve the unique id of a source file.
fn resolve(&self, path: &Path) -> FileResult<SourceId>;
/// 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.
///
/// Default: Empty path.
pub root: PathBuf,
/// The scope containing definitions that are available everywhere.
///
/// Default: Typst's standard library.
pub std: Scope,
/// Defines which standard library items fulfill which syntactical roles.
///
/// Default: Typst's standard library's role map.
pub roles: RoleMap,
/// The default properties for page size, font selection and so on.
///
/// Default: Empty style map.
pub styles: StyleMap,
}
impl Default for Config {
fn default() -> Self {
Self {
root: PathBuf::new(),
std: library::scope(),
styles: StyleMap::new(),
roles: library::roles(),
}
}
}
/// Definition of certain standard library items the language is aware of.
#[derive(Debug, Clone, Hash)]
pub struct RoleMap {
pub strong: fn(Content) -> Content,
pub emph: fn(Content) -> Content,
pub raw: fn(EcoString, Option<EcoString>, bool) -> Content,
pub link: fn(EcoString) -> Content,
pub ref_: fn(EcoString) -> Content,
pub heading: fn(NonZeroUsize, Content) -> Content,
pub list_item: fn(Content) -> Content,
pub enum_item: fn(Option<usize>, Content) -> Content,
pub desc_item: fn(Content, Content) -> Content,
}