1 files changed, 92 insertions, 0 deletions
diff --git a/crates/typst-library/src/shared/ext.rs b/crates/typst-library/src/shared/ext.rs
new file mode 100644
index 00000000..d7c80a30
--- /dev/null
+++ b/crates/typst-library/src/shared/ext.rs
@@ -0,0 +1,92 @@
+//! Extension traits.
+
+use crate::layout::{AlignElem, MoveElem, PadElem};
+use crate::prelude::*;
+use crate::text::{EmphElem, FontFamily, FontList, StrongElem, TextElem, UnderlineElem};
+
+/// Additional methods on content.
+pub trait ContentExt {
+    /// Make this content strong.
+    fn strong(self) -> Self;
+
+    /// Make this content emphasized.
+    fn emph(self) -> Self;
+
+    /// Underline this content.
+    fn underlined(self) -> Self;
+
+    /// Link the content somewhere.
+    fn linked(self, dest: Destination) -> Self;
+
+    /// Make the content linkable by `.linked(Destination::Location(loc))`.
+    ///
+    /// Should be used in combination with [`Location::variant`].
+    fn backlinked(self, loc: Location) -> Self;
+
+    /// Set alignments for this content.
+    fn aligned(self, aligns: Axes<Option<GenAlign>>) -> Self;
+
+    /// Pad this content at the sides.
+    fn padded(self, padding: Sides<Rel<Length>>) -> Self;
+
+    /// Transform this content's contents without affecting layout.
+    fn moved(self, delta: Axes<Rel<Length>>) -> Self;
+}
+
+impl ContentExt for Content {
+    fn strong(self) -> Self {
+        StrongElem::new(self).pack()
+    }
+
+    fn emph(self) -> Self {
+        EmphElem::new(self).pack()
+    }
+
+    fn underlined(self) -> Self {
+        UnderlineElem::new(self).pack()
+    }
+
+    fn linked(self, dest: Destination) -> Self {
+        self.styled(MetaElem::set_data(vec![Meta::Link(dest)]))
+    }
+
+    fn backlinked(self, loc: Location) -> Self {
+        let mut backlink = Content::empty();
+        backlink.set_location(loc);
+        self.styled(MetaElem::set_data(vec![Meta::Elem(backlink)]))
+    }
+
+    fn aligned(self, aligns: Axes<Option<GenAlign>>) -> Self {
+        self.styled(AlignElem::set_alignment(aligns))
+    }
+
+    fn padded(self, padding: Sides<Rel<Length>>) -> Self {
+        PadElem::new(self)
+            .with_left(padding.left)
+            .with_top(padding.top)
+            .with_right(padding.right)
+            .with_bottom(padding.bottom)
+            .pack()
+    }
+
+    fn moved(self, delta: Axes<Rel<Length>>) -> Self {
+        MoveElem::new(self).with_dx(delta.x).with_dy(delta.y).pack()
+    }
+}
+
+/// Additional methods for style lists.
+pub trait StylesExt {
+    /// Set a font family composed of a preferred family and existing families
+    /// from a style chain.
+    fn set_family(&mut self, preferred: FontFamily, existing: StyleChain);
+}
+
+impl StylesExt for Styles {
+    fn set_family(&mut self, preferred: FontFamily, existing: StyleChain) {
+        self.set(TextElem::set_font(FontList(
+            std::iter::once(preferred)
+                .chain(TextElem::font_in(existing))
+                .collect(),
+        )));
+    }
+}