Add forms 2 and 3 of LaTeX fragment.

src/parser/latex_fragment.rs

@@ -23,7 +23,11 @@ pub fn latex_fragment<'r, 's>(
     context: Context<'r, 's>,
     input: &'s str,
 ) -> Res<&'s str, LatexFragment<'s>> {
-    let (remaining, _) = alt((parser_with_context!(raw_latex_fragment)(context),))(input)?;
+    let (remaining, _) = alt((
+        parser_with_context!(raw_latex_fragment)(context),
+        parser_with_context!(escaped_parenthesis_fragment)(context),
+        parser_with_context!(escaped_bracket_fragment)(context),
+    ))(input)?;
     let (remaining, _) = space0(remaining)?;
     let source = get_consumed(input, remaining);
     Ok((remaining, LatexFragment { source }))
@@ -72,3 +76,41 @@ fn brackets<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, &'
     ))(input)?;
     Ok((remaining, body))
 }
+
+#[tracing::instrument(ret, level = "debug")]
+fn escaped_parenthesis_fragment<'r, 's>(
+    context: Context<'r, 's>,
+    input: &'s str,
+) -> Res<&'s str, &'s str> {
+    let (remaining, _) = tag("\\(")(input)?;
+    let (remaining, _) = recognize(many_till(
+        anychar,
+        peek(alt((
+            parser_with_context!(exit_matcher_parser)(context),
+            tag("\\)"),
+        ))),
+    ))(remaining)?;
+    let (remaining, _) = tag("\\)")(remaining)?;
+
+    let source = get_consumed(input, remaining);
+    Ok((remaining, source))
+}
+
+#[tracing::instrument(ret, level = "debug")]
+fn escaped_bracket_fragment<'r, 's>(
+    context: Context<'r, 's>,
+    input: &'s str,
+) -> Res<&'s str, &'s str> {
+    let (remaining, _) = tag("\\[")(input)?;
+    let (remaining, _) = recognize(many_till(
+        anychar,
+        peek(alt((
+            parser_with_context!(exit_matcher_parser)(context),
+            tag("\\]"),
+        ))),
+    ))(remaining)?;
+    let (remaining, _) = tag("\\]")(remaining)?;
+
+    let source = get_consumed(input, remaining);
+    Ok((remaining, source))
+}