Initial bar

src/bar.rs

@@ -0,0 +1,106 @@
+use std::fmt::Display;
+
+use crate::{chords::Chord, Note};
+
+pub enum BarElement<C>
+where
+    C: Chord<IntoIter = <Vec<Note> as IntoIterator>::IntoIter>,
+{
+    Silence(u8),
+    Chord(C, u8),
+}
+
+impl<C> Display for BarElement<C>
+where
+    C: Display + Chord<IntoIter = <Vec<Note> as IntoIterator>::IntoIter>,
+{
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            BarElement::Silence(_) => write!(f, "_"),
+            BarElement::Chord(chord, _) => write!(f, "{}", chord),
+        }
+    }
+}
+
+pub struct Bar<C>(Vec<BarElement<C>>)
+where
+    C: Chord<IntoIter = <Vec<Note> as IntoIterator>::IntoIter>;
+
+impl<C> Bar<C>
+where
+    C: Chord<IntoIter = <Vec<Note> as IntoIterator>::IntoIter>,
+{
+    pub fn new() -> Self {
+        Self(vec![])
+    }
+
+    pub fn with_chord(self, chord: C, fraction: u8) -> Self {
+        let mut items = self.0;
+        items.push(BarElement::Chord(chord, fraction));
+        Self(items)
+    }
+
+    pub fn with_silence(self, fraction: u8) -> Self {
+        let mut items = self.0;
+        items.push(BarElement::Silence(fraction));
+        Self(items)
+    }
+}
+
+impl<C> Default for Bar<C>
+where
+    C: Chord<IntoIter = <Vec<Note> as IntoIterator>::IntoIter>,
+{
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<C> Display for Bar<C>
+where
+    C: Display + Chord<IntoIter = <Vec<Note> as IntoIterator>::IntoIter>,
+{
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let s = self
+            .0
+            .iter()
+            .map(|e| e.to_string())
+            .collect::<Vec<String>>()
+            .join(" - ");
+        write!(f, "{s}")
+    }
+}
+
+pub fn show<C>(bars: impl Iterator<Item = Bar<C>>) -> String
+where
+    C: Display + Chord<IntoIter = <Vec<Note> as IntoIterator>::IntoIter>,
+{
+    let s = bars
+        .map(|b| b.to_string())
+        .collect::<Vec<String>>()
+        .join(" | ");
+    format!("| {s} |")
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{C, G};
+
+    use super::*;
+
+    #[test]
+    fn display() {
+        let bar = Bar::new().with_chord(C.major(), 2).with_chord(G.major(), 2);
+        assert_eq!(bar.to_string(), "C - G");
+    }
+
+    #[test]
+    fn displa_bars() {
+        let bar1 = Bar::new().with_chord(C.major(), 2).with_chord(G.major(), 2);
+        let bar2 = Bar::new().with_chord(C.major(), 2).with_chord(G.major(), 2);
+        let bars = [bar1, bar2];
+
+        let s = show(bars.into_iter());
+        assert_eq!(s, "| C - G | C - G |")
+    }
+}

src/lib.rs

@@ -21,9 +21,11 @@
 //! println!("Dom7 C: {chord:X}");
 //! ```
 
+mod bar;
 pub mod chords;
 mod note;
 mod tone;
 
+pub use bar::*;
 pub use note::*;
 pub use tone::*;