Use a single function for finding all keywords.

src/parser/in_buffer_settings.rs

@@ -0,0 +1,28 @@
+use nom::branch::alt;
+use nom::bytes::complete::tag_no_case;
+use nom::character::complete::anychar;
+use nom::combinator::map;
+use nom::multi::many0;
+use nom::multi::many_till;
+
+use super::keyword::filtered_keyword;
+use super::OrgSource;
+use crate::error::Res;
+use crate::types::Keyword;
+
+pub fn scan_for_in_buffer_settings<'s>(
+    input: OrgSource<'s>,
+) -> Res<OrgSource<'s>, Vec<Keyword<'s>>> {
+    // TODO: Optimization idea: since this is slicing the OrgSource at each character, it might be more efficient to do a parser that uses a search function like take_until, and wrap it in a function similar to consumed but returning the input along with the normal output, then pass all of that into a verify that confirms we were at the start of a line using the input we just returned.
+
+    let keywords = many0(map(
+        many_till(anychar, filtered_keyword(in_buffer_settings_key)),
+        |(_, kw)| kw,
+    ))(input);
+    keywords
+}
+
+#[cfg_attr(feature = "tracing", tracing::instrument(ret, level = "debug"))]
+fn in_buffer_settings_key<'s>(input: OrgSource<'s>) -> Res<OrgSource<'s>, OrgSource<'s>> {
+    alt((tag_no_case("todo"), tag_no_case("setupfile")))(input)
+}