Create structure for subscript and superscript.

src/parser/object.rs

@@ -26,6 +26,8 @@ pub enum Object<'s> {
     LineBreak(LineBreak<'s>),
     Target(Target<'s>),
     StatisticsCookie(StatisticsCookie<'s>),
+    Subscript(Subscript<'s>),
+    Superscript(Superscript<'s>),
 }
 
 #[derive(Debug, PartialEq)]
@@ -167,6 +169,16 @@ pub struct StatisticsCookie<'s> {
     pub source: &'s str,
 }
 
+#[derive(Debug, PartialEq)]
+pub struct Subscript<'s> {
+    pub source: &'s str,
+}
+
+#[derive(Debug, PartialEq)]
+pub struct Superscript<'s> {
+    pub source: &'s str,
+}
+
 impl<'s> Source<'s> for Object<'s> {
     fn get_source(&'s self) -> &'s str {
         match self {
@@ -194,6 +206,8 @@ impl<'s> Source<'s> for Object<'s> {
             Object::LineBreak(obj) => obj.source,
             Object::Target(obj) => obj.source,
             Object::StatisticsCookie(obj) => obj.source,
+            Object::Subscript(obj) => obj.source,
+            Object::Superscript(obj) => obj.source,
         }
     }
 }
@@ -335,3 +349,15 @@ impl<'s> Source<'s> for StatisticsCookie<'s> {
         self.source
     }
 }
+
+impl<'s> Source<'s> for Subscript<'s> {
+    fn get_source(&'s self) -> &'s str {
+        self.source
+    }
+}
+
+impl<'s> Source<'s> for Superscript<'s> {
+    fn get_source(&'s self) -> &'s str {
+        self.source
+    }
+}