diff --git a/four-bar-ui/src/app/proj/impl_proj.rs b/four-bar-ui/src/app/proj/impl_proj.rs
index 212ee823..08aa1c1e 100644
--- a/four-bar-ui/src/app/proj/impl_proj.rs
+++ b/four-bar-ui/src/app/proj/impl_proj.rs
@@ -1,5 +1,6 @@
 use super::*;
 use four_bar::{csv, efd, fb, NormFourBar, SNormFourBar};
+use std::path::Path;
 
 macro_rules! hotkey {
     ($ui:ident, $mod1:ident + $key:ident) => {
@@ -88,7 +89,7 @@ impl Project {
         fn name(self: &Self) -> String;
         fn preload(self: &mut Self);
         fn set_path(self: &mut Self, path: PathBuf);
-        fn path(self: &Self) -> Option<&PathBuf>;
+        fn path(self: &Self) -> Option<&Path>;
         fn is_unsaved(self: &Self) -> bool;
         fn mark_saved(self: &mut Self);
     }
@@ -286,7 +287,7 @@ where
                 io::save_csv_ask(&get_curve(*pivot, &self.fb, cfg.res));
             }
             if small_btn(ui, "🗐", "Copy") {
-                let t = csv::csv_string(get_curve(*pivot, &self.fb, cfg.res)).unwrap();
+                let t = csv::to_string(get_curve(*pivot, &self.fb, cfg.res)).unwrap();
                 ui.output_mut(|s| s.copied_text = t);
             }
         });
@@ -358,24 +359,22 @@ where
         if cfg!(target_arch = "wasm32") {
             return;
         }
-        if let Some(fb) = self
-            .path
-            .as_ref()
-            .and_then(|p| std::fs::File::open(p).ok())
-            .and_then(|r| ron::de::from_reader(r).ok())
-        {
-            if self.fb != fb {
+        // FIXME: Try block, ignore errors
+        (|| {
+            let r = std::fs::File::open(self.path.as_ref()?).ok()?;
+            if self.fb != ron::de::from_reader(r).ok()? {
                 self.unsaved = true;
             }
-        }
+            Some(())
+        })();
     }
 
     fn set_path(&mut self, path: PathBuf) {
         self.path.replace(path);
     }
 
-    fn path(&self) -> Option<&PathBuf> {
-        self.path.as_ref()
+    fn path(&self) -> Option<&Path> {
+        self.path.as_deref()
     }
 
     fn is_unsaved(&self) -> bool {
diff --git a/four-bar-ui/src/app/syn.rs b/four-bar-ui/src/app/syn.rs
index 09a9e131..a8ccaae7 100644
--- a/four-bar-ui/src/app/syn.rs
+++ b/four-bar-ui/src/app/syn.rs
@@ -140,8 +140,8 @@ impl Synthesis {
         ui.horizontal_wrapped(|ui| {
             if ui.button("🗐 Copy CSV").clicked() {
                 let text = match &self.target {
-                    io::Curve::P(t) => csv::csv_string(t).unwrap(),
-                    io::Curve::S(t) => csv::csv_string(t).unwrap(),
+                    io::Curve::P(t) => csv::to_string(t).unwrap(),
+                    io::Curve::S(t) => csv::to_string(t).unwrap(),
                 };
                 ui.output_mut(|s| s.copied_text = text);
             }
diff --git a/four-bar-ui/src/io.rs b/four-bar-ui/src/io.rs
index 819fbe0e..fc4110fa 100644
--- a/four-bar-ui/src/io.rs
+++ b/four-bar-ui/src/io.rs
@@ -288,13 +288,13 @@ where
 
 pub(crate) fn save_csv_ask<S>(c: &[S])
 where
-    S: serde::Serialize + Clone,
+    S: serde::Serialize,
 {
     save_ask(
         "curve.csv",
         CSV_FMT,
         CSV_EXT,
-        |w| csv::dump_csv(w, c),
+        |w| csv::to_writer(w, c),
         |_| (),
     );
 }
@@ -372,11 +372,11 @@ impl Curve {
     where
         R: std::io::Read + std::io::Seek,
     {
-        if let Ok(c) = csv::parse_csv(&mut r) {
+        if let Ok(c) = csv::from_reader(&mut r) {
             Ok(Self::S(c))
         } else {
             r.rewind()?;
-            Ok(Self::P(csv::parse_csv(r)?))
+            Ok(Self::P(csv::from_reader(r)?))
         }
     }
 
diff --git a/four-bar/src/csv.rs b/four-bar/src/csv.rs
index d4527025..d20a16fe 100644
--- a/four-bar/src/csv.rs
+++ b/four-bar/src/csv.rs
@@ -2,32 +2,32 @@
 pub use csv::Error;
 use csv::{ReaderBuilder, Writer};
 use serde::{de::DeserializeOwned, Serialize};
+use std::io::ErrorKind::InvalidData;
 
 /// Parse CSV from string.
-pub fn parse_csv<D, R>(r: R) -> Result<Vec<D>, Error>
+pub fn from_reader<R, D>(r: R) -> Result<Vec<D>, Error>
 where
     R: std::io::Read,
     D: DeserializeOwned,
 {
-    let data = ReaderBuilder::new()
+    ReaderBuilder::new()
         .has_headers(false)
         .comment(Some(b'#'))
         .from_reader(r)
         .deserialize()
-        .collect::<Result<Vec<_>, _>>()?;
-    if data.is_empty() {
-        Err(std::io::Error::new(std::io::ErrorKind::InvalidData, "No data").into())
-    } else {
-        Ok(data)
-    }
+        .collect::<Result<Vec<_>, _>>()
+        .and_then(|data| match data.is_empty() {
+            true => Err(std::io::Error::new(InvalidData, "Empty data"))?,
+            false => Ok(data),
+        })
 }
 
 /// Dump CSV to a writer.
-pub fn dump_csv<'a, W, C, S>(w: W, c: C) -> Result<(), csv::Error>
+pub fn to_writer<W, C, S>(w: W, c: C) -> Result<(), csv::Error>
 where
     W: std::io::Write,
     C: AsRef<[S]>,
-    S: Serialize + Clone + 'a,
+    S: Serialize,
 {
     let mut w = Writer::from_writer(w);
     c.as_ref().iter().try_for_each(|c| w.serialize(c))?;
@@ -36,12 +36,12 @@ where
 }
 
 /// Dump CSV to string.
-pub fn csv_string<'a, C, S>(c: C) -> Result<String, csv::Error>
+pub fn to_string<C, S>(c: C) -> Result<String, csv::Error>
 where
     C: AsRef<[S]>,
-    S: Serialize + Clone + 'a,
+    S: Serialize,
 {
     let mut w = Vec::new();
-    dump_csv(&mut w, c)?;
+    to_writer(&mut w, c)?;
     Ok(String::from_utf8(w).unwrap())
 }
diff --git a/four-bar/src/plot.rs b/four-bar/src/plot.rs
index 178d8ec9..161cb439 100644
--- a/four-bar/src/plot.rs
+++ b/four-bar/src/plot.rs
@@ -579,10 +579,7 @@ impl<'a, 'b, M: Clone, C: Clone> FigureBase<'a, 'b, M, C> {
     #[inline]
     fn get_family(&self) -> &str {
         const DEFAULT_FONT: &str = "Times New Roman";
-        self.font_family
-            .as_ref()
-            .map(|s| s.as_ref())
-            .unwrap_or(DEFAULT_FONT)
+        self.font_family.as_deref().unwrap_or(DEFAULT_FONT)
     }
 
     pub(crate) fn get_font(&self) -> TextStyle {