[rust] Proverb

1 files changed, 15 insertions, 0 deletions

diff --git a/proverb/src/lib.rs b/proverb/src/lib.rs
new file mode 100644
index 0000000..1046553
--- /dev/null
+++ b/proverb/src/lib.rs
@@ -0,0 +1,15 @@
+use std::iter;
+
+pub fn build_proverb(list: &[&str]) -> String {
+    if list.is_empty() {
+        String::new()
+    } else {
+        let reason = |(a, b)| format!("For want of a {} the {} was lost.\n", a, b);
+        let bitter_end = format!("And all for the want of a {}.", list[0]);
+        list.iter()
+            .zip(list.iter().skip(1)) // .window(2) also works here
+            .map(reason)
+            .chain(iter::once(bitter_end))
+            .collect()
+    }
+}