Starting to separate the context and parsed tokens into their own modules.

src/context/exiting.rs

@@ -0,0 +1,20 @@
+#[derive(Debug, Copy, Clone)]
+pub enum ExitClass {
+    /// Headlines and sections.
+    Document = 1,
+
+    /// Elements who take priority over beta elements when matching.
+    Alpha = 20,
+
+    /// Elements who cede priority to alpha elements when matching.
+    Beta = 300,
+
+    /// Elements who cede priority to alpha and beta elements when matching.
+    Gamma = 4000,
+}
+
+impl std::fmt::Display for ExitClass {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{:?}", self)
+    }
+}