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Task/String-matching/D/string-matching.d

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+void main() {
+    import std.stdio;
+    import std.algorithm: startsWith, endsWith, find, countUntil;
+
+    "abcd".startsWith("ab").writeln;      // true
+    "abcd".endsWith("zn").writeln;        // false
+    "abab".find("bb").writeln;            // empty array (no match)
+    "abcd".find("bc").writeln;            // "bcd" (substring start
+                                           //        at match)
+    "abab".countUntil("bb").writeln;      // -1 (no match)
+    "abab".countUntil("ba").writeln;      //  1 (index of 1st match)
+
+    // std.algorithm.startsWith also works on arrays and ranges:
+    [1, 2, 3].countUntil(3).writeln;      //  2
+    [1, 2, 3].countUntil([2, 3]).writeln; //  1
+}