master > master: code-rust - init

code/rust/src/core/utils.rs

@@ -11,15 +11,45 @@ use self::regex::Regex;
 // ----------------------------------------------------------------
 
 /// Constructs RegEx and panics if error.
+#[allow(dead_code)]
 pub fn construct_regex(pattern: &str) -> Regex {
     return Regex::new(pattern)
         .expect("Invalid regex construction!");
 }
 
 // ----------------------------------------------------------------
-// METHOD hello world
+// METHODS values
 // ----------------------------------------------------------------
 
-pub fn greet() {
-    println!("Hello world!");
+pub fn min<T>(x: T, y: T) -> T
+    where T: PartialOrd
+{
+    return if y < x { y } else { x };
+}
+
+// ----------------------------------------------------------------
+// METHODS Vectors
+// ----------------------------------------------------------------
+
+pub fn restrict<T>(x: &mut Vec<T>, i: usize, j: usize) -> Vec<T>
+    where T: Clone
+{
+    return x[i..j].iter()
+        .cloned()
+        .collect::<Vec<T>>();
+}
+
+pub fn remove_last<T>(x: &mut Vec<T>) -> Vec<T>
+    where T: Clone
+{
+    let n = x.len();
+    return restrict::<T>(x, 0, n-1);
+}
+
+#[allow(dead_code)]
+pub fn remove_first<T>(x: &mut Vec<T>) -> Vec<T>
+    where T: Clone
+{
+    let n = x.len();
+    return restrict::<T>(x, 0, n);
 }