Split out four new crates (#5302)

1 files changed, 98 insertions, 0 deletions

diff --git a/crates/typst-library/src/layout/columns.rs b/crates/typst-library/src/layout/columns.rs
new file mode 100644
index 00000000..f2f36441
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+++ b/crates/typst-library/src/layout/columns.rs
@@ -0,0 +1,98 @@
+use std::num::NonZeroUsize;
+
+use crate::diag::SourceResult;
+use crate::engine::Engine;
+use crate::foundations::{elem, Content, NativeElement, Packed, Show, StyleChain};
+use crate::layout::{BlockElem, Length, Ratio, Rel};
+
+/// Separates a region into multiple equally sized columns.
+///
+/// The `column` function lets you separate the interior of any container into
+/// multiple columns. It will currently not balance the height of the columns.
+/// Instead, the columns will take up the height of their container or the
+/// remaining height on the page. Support for balanced columns is planned for
+/// the future.
+///
+/// # Page-level columns { #page-level }
+/// If you need to insert columns across your whole document, use the `{page}`
+/// function's [`columns` parameter]($page.columns) instead. This will create
+/// the columns directly at the page-level rather than wrapping all of your
+/// content in a layout container. As a result, things like
+/// [pagebreaks]($pagebreak), [footnotes]($footnote), and [line
+/// numbers]($par.line) will continue to work as expected. For more information,
+/// also read the [relevant part of the page setup
+/// guide]($guides/page-setup-guide/#columns).
+///
+/// # Breaking out of columns { #breaking-out }
+/// To temporarily break out of columns (e.g. for a paper's title), use
+/// parent-scoped floating placement:
+///
+/// ```example:single
+/// #set page(columns: 2, height: 150pt)
+///
+/// #place(
+///   top + center,
+///   scope: "parent",
+///   float: true,
+///   text(1.4em, weight: "bold")[
+///     My document
+///   ],
+/// )
+///
+/// #lorem(40)
+/// ```
+#[elem(Show)]
+pub struct ColumnsElem {
+    /// The number of columns.
+    #[positional]
+    #[default(NonZeroUsize::new(2).unwrap())]
+    pub count: NonZeroUsize,
+
+    /// The size of the gutter space between each column.
+    #[resolve]
+    #[default(Ratio::new(0.04).into())]
+    pub gutter: Rel<Length>,
+
+    /// The content that should be layouted into the columns.
+    #[required]
+    pub body: Content,
+}
+
+impl Show for Packed<ColumnsElem> {
+    fn show(&self, engine: &mut Engine, _: StyleChain) -> SourceResult<Content> {
+        Ok(BlockElem::multi_layouter(self.clone(), engine.routines.layout_columns)
+            .pack()
+            .spanned(self.span()))
+    }
+}
+
+/// Forces a column break.
+///
+/// The function will behave like a [page break]($pagebreak) when used in a
+/// single column layout or the last column on a page. Otherwise, content after
+/// the column break will be placed in the next column.
+///
+/// # Example
+/// ```example
+/// #set page(columns: 2)
+/// Preliminary findings from our
+/// ongoing research project have
+/// revealed a hitherto unknown
+/// phenomenon of extraordinary
+/// significance.
+///
+/// #colbreak()
+/// Through rigorous experimentation
+/// and analysis, we have discovered
+/// a hitherto uncharacterized process
+/// that defies our current
+/// understanding of the fundamental
+/// laws of nature.
+/// ```
+#[elem(title = "Column Break")]
+pub struct ColbreakElem {
+    /// If `{true}`, the column break is skipped if the current column is
+    /// already empty.
+    #[default(false)]
+    pub weak: bool,
+}