Add page header

examples/computer-science/main.typ

@@ -3,7 +3,7 @@
 
 #show: khw.with(
   title: [Homework 3],
-  course: "CS 250",
+  course: "CS 250: Computer Architecture",
   author: "Kian Kasad",
 )
 

khw.typ

@@ -72,17 +72,36 @@
   set math.equation(numbering: "(1)")
   set page(numbering: "1")
 
-  // Title block {{{2
-  if title != none {
-    align(center, {
-      text(weight: "bold", size: 18pt, {
+  // Page header {{{2
+  set page(
+    header-ascent: 50%,
+    header: context {
+      set text(10pt)
+      let pagenum = counter(page).get().first()
+      if pagenum != 1 {
         if course != none {
-          course + [ --- ]
+          if type(course) == str {
+            course.replace(regex("(:\s+|\s+-+\s+).*$"), "")
+          } else {
+            course
+          }
+          [ --- ]
         }
         title
-      })
-      parbreak()
-      author
+        h(1fr)
+        author
+      }
+    }
+  )
+
+  // Title block {{{2
+  if title != none {
+    align(center, {
+      text(18pt, weight: "bold", title)
+      linebreak()
+      text(12pt, course)
+      linebreak()
+      text(12pt, author)
     })
     v(1cm, weak: true)
   }

manual.typ

@@ -137,8 +137,9 @@ it to all content using a show rule:
 )[Document setup code.]
 
 The `title` and `author` fields are used to print a title
-block on the first page, as well as to set the document's
-metadata using ```typc document()```.
+block on the first page, set the document's metadata using
+```typc document()```, and print a header on every page except
+the first.
 
 The `khw()` function supports the following optional parameters:
 
@@ -188,7 +189,20 @@ used to set default options for the ```typc problem()``` and
   handle storing functions, but I have not verified this.
 ]
 
-#pagebreak()
+== Page header
+On every page except the first, a header will be displayed,
+consisting of the course and title on the left and the author
+on the right.
+
+The course is preprocessed in a special way: if the `course`
+parameter to the `khw()` function was a string, a _course
+prefix separator_ and everything after it is removed.
+The course prefix separator is anything that matches the
+following regular expression: ```regex (:\s+|\s+-+\s+)```.
+This allows you to print something like "CS 250: Computer
+Architecture" in the title block while still keeping the
+header short enough.
+
 == Typesetting problems
 Use the `problem()` function to typeset a problem. The
 function takes a non-optional content argument which can be