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authorAbdou Seck <djily02016@gmail.com>2019-12-16 08:34:30 -0500
committerAbdou Seck <djily02016@gmail.com>2019-12-16 09:12:13 -0500
commit0c85dc1193978b5165491b99cc4922caf8d14a65 (patch)
tree52dfb7d89525b540ce896e4eacd525fdfa8adef5 /exercises/conversions/as_ref_mut.rs
parentfe10e06c3733ddb4a21e90d09bf79bfe618e97ce (diff)
feat: Add type conversion and parsing exercises
Diffstat (limited to 'exercises/conversions/as_ref_mut.rs')
-rw-r--r--exercises/conversions/as_ref_mut.rs36
1 files changed, 36 insertions, 0 deletions
diff --git a/exercises/conversions/as_ref_mut.rs b/exercises/conversions/as_ref_mut.rs
new file mode 100644
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+++ b/exercises/conversions/as_ref_mut.rs
@@ -0,0 +1,36 @@
+// AsRef and AsMut allow for cheap reference-to-reference conversions.
+// Read more about them at https://doc.rust-lang.org/std/convert/trait.AsRef.html
+// and https://doc.rust-lang.org/std/convert/trait.AsMut.html, respectively.
+
+// Obtain the number of bytes (not characters) in the given argument
+// Add the AsRef trait appropriately as a trait bound
+fn byte_counter<T>(arg: T) -> usize {
+ arg.as_ref().as_bytes().len()
+}
+
+// Obtain the number of characters (not bytes) in the given argument
+// Add the AsRef trait appropriately as a trait bound
+fn char_counter<T>(arg: T) -> usize {
+ arg.as_ref().chars().collect::<Vec<_>>().len()
+}
+
+fn main() {
+ let s = "Café au lait";
+ println!("{}", char_counter(s));
+ println!("{}", byte_counter(s));
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ #[test]
+ fn different_counts() {
+ let s = "Café au lait";
+ assert_ne!(char_counter(s), byte_counter(s));
+ }
+ fn same_counts() {
+ let s = "Cafe au lait";
+ assert_eq!(char_counter(s), byte_counter(s));
+ }
+} \ No newline at end of file