Add std::cmp.min and std::cmp.max

These methods take two values and return the minimum and maximum value
respectively.

Changelog: added

libstd/src/std/cmp.inko

@@ -106,3 +106,25 @@ trait pub Contains[T] {
   # Returns `true` if the given value is contained in `self`.
   fn pub contains?(value: ref T) -> Bool
 }
+
+# Returns the minimum of two values.
+#
+# # Examples
+#
+#     import std::cmp::(min)
+#
+#     min(10, 5) # => 5
+fn pub min[T: Compare](a: T, b: T) -> T {
+  if a <= b { a } else { b }
+}
+
+# Returns the maximum of two values.
+#
+# # Examples
+#
+#     import std::cmp::(max)
+#
+#     max(10, 5) # => 10
+fn pub max[T: Compare](a: T, b: T) -> T {
+  if a >= b { a } else { b }
+}

libstd/test/std/test_cmp.inko

@@ -1,5 +1,5 @@
 import helpers::(fmt)
-import std::cmp::(Compare, Equal, Ordering)
+import std::cmp::(Compare, Equal, Ordering, max, min)
 import std::test::Tests
 
 class enum Letter {
@@ -82,4 +82,16 @@ fn pub tests(t: mut Tests) {
     t.true(Letter.A == Letter.A)
     t.true(Letter.A != Letter.B)
   }
+
+  t.test('cmp.min') fn (t) {
+    t.equal(min(10, 10), 10)
+    t.equal(min(10, 5), 5)
+    t.equal(min(5, 10), 5)
+  }
+
+  t.test('cmp.max') fn (t) {
+    t.equal(max(10, 10), 10)
+    t.equal(max(10, 5), 10)
+    t.equal(max(5, 10), 10)
+  }
 }