Keep StyledString markup-agnostic, push trait to methods

src/utils/markup/mod.rs

@@ -19,50 +19,54 @@ pub trait Markup {
 
     /// Parses text and return the styled spans.
     fn parse<'a>(input: &'a str) -> Result<Vec<Span<'a>>, Self::Error>;
-}
 
-type StyledHandle = OwningHandle<StringRef, Vec<Span<'static>>>;
-
-/// A String that parses a markup language.
-pub struct StyledString<M> {
-    content: StyledHandle,
-    _phantom: PhantomData<M>,
-}
-
-impl<M> StyledString<M>
-where
-    M: Markup,
-{
-    fn make_handle<S: Into<String>>(
-        content: S
-    ) -> Result<StyledHandle, M::Error> {
-        let content = content.into();
-        OwningHandle::try_new(StringRef::new(content), |input| {
-            M::parse(unsafe { &*input })
-        })
-    }
-
-    /// Creates a new styled string, parsing the given content.
-    pub fn new<S>(content: S) -> Result<Self, M::Error>
+    /// Returns a string and its parsed spans.
+    ///
+    /// Generates a self-borrowing struct containing the source string, as well
+    /// as the styled spans borrowing this string.
+    fn make_handle<S>(input: S) -> Result<StyledHandle, Self::Error>
     where
         S: Into<String>,
     {
-        let content = Self::make_handle(content)?;
-        Ok(StyledString {
-            content,
-            _phantom: PhantomData,
+        let input = input.into();
+        OwningHandle::try_new(StringRef::new(input), |input| {
+            Self::parse(unsafe { &*input })
         })
     }
+}
+
+/// Holds both parsed spans, and the input string they borrow.
+///
+/// This is used to pass around a parsed string.
+pub type StyledHandle = OwningHandle<StringRef, Vec<Span<'static>>>;
+
+/// A String that parses a markup language.
+pub struct StyledString {
+    content: StyledHandle,
+}
+
+impl StyledString {
+
+    /// Creates a new styled string, parsing the given content.
+    pub fn new<S, M>(content: S) -> Result<Self, M::Error>
+    where
+        S: Into<String>,
+        M: Markup,
+    {
+        let content = M::make_handle(content)?;
+        Ok(StyledString { content })
+    }
 
     /// Sets the content of this string.
     ///
     /// The content will be parsed; if an error is found,
     /// it will be returned here (and the content will be unchanged).
-    pub fn set_content<S>(&mut self, content: S) -> Result<(), M::Error>
+    pub fn set_content<S, M>(&mut self, content: S) -> Result<(), M::Error>
     where
         S: Into<String>,
+        M: Markup,
     {
-        self.content = Self::make_handle(content)?;
+        self.content = M::make_handle(content)?;
 
         Ok(())
     }