rust go brr

src/main.rs

@@ -1,6 +1,9 @@
 mod compile_data;
+mod map_ok;
 mod raw_data;
 
+use map_ok::MapOkTrait;
+
 use crate::compile_data::{DpsRole, JobStats, Role};
 use crate::raw_data::RawJobStats;
 
@@ -17,10 +20,8 @@ fn get_job_stats(lodestone_ids: &[usize]) -> anyhow::Result<Vec<Vec<JobStats>>>
     let raw_data = output.stdout.lines();
     let data: Vec<Result<Vec<JobStats>, _>> = raw_data
         .map_while(Result::ok)
-        .map(|raw| serde_json::from_str(&raw))
-        .map(|raw_stats: Result<Vec<RawJobStats>, _>| {
-            raw_stats.map(|raw| raw.into_iter().map(|r| r.into()).collect())
-        })
+        .map(|buf| serde_json::from_str::<Vec<RawJobStats>>(&buf))
+        .map_ok(|raw| raw.into_iter().map(|r| r.into()).collect())
         .map(|stats| stats.map_err(|err| anyhow::anyhow!(err)))
         .collect();
 

src/map_ok.rs

@@ -0,0 +1,33 @@
+#[derive(Clone)]
+pub struct MapOkIterator<I, F> {
+    iter: I,
+    f: F,
+}
+
+impl<A, B, E, I, F> Iterator for MapOkIterator<I, F>
+where
+    F: FnMut(A) -> B,
+    I: Iterator<Item = Result<A, E>>,
+{
+    type Item = Result<B, E>;
+
+    #[inline]
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next().map(|x| x.map(&mut self.f))
+    }
+}
+
+pub trait MapOkTrait {
+    fn map_ok<F, A, B, E>(self, func: F) -> MapOkIterator<Self, F>
+    where
+        Self: Sized + Iterator<Item = Result<A, E>>,
+        F: FnMut(A) -> B,
+    {
+        MapOkIterator {
+            iter: self,
+            f: func,
+        }
+    }
+}
+
+impl<I, T, E> MapOkTrait for I where I: Sized + Iterator<Item = Result<T, E>> {}