funclang: Finished code of assignment 2.5.

.gitignore

@@ -16,5 +16,6 @@ robotica/
 *.toc
 *.cmi
 *.cmo
+*.exe
 *#
 *~

funclang-taddeus/series2/ass5.ml

@@ -2,3 +2,90 @@
 let isLeapYear y =
     y > 1582 && y mod 4 = 0 && (y mod 100 != 0 || y mod 400 = 0)
 ;;
+
+(* Test the isLeapYear function with a number of known leap years *)
+let test_isLeapYear y expect =
+    let yields = isLeapYear y in
+    Printf.printf "%d -> %s, (should be %b, yields %b)\n"
+        y (if yields = expect then "success" else "failure") expect yields
+;;
+
+test_isLeapYear 1500 false;;
+test_isLeapYear 1900 false;;
+test_isLeapYear 1904 true;;
+
+(* Give a proper English character string representation of a date *)
+let date2str day month year =
+    if day < 1 || day > 31 || month < 1 || month > 12 || year < 0 then
+        raise Exit
+    else
+        (* Get the textual postfix of a day number *)
+        let getDayPostfix day =
+            match day with
+              1 | 21 | 31 -> "st"
+            | 2 | 22 -> "nd"
+            | 3 | 23 -> "rd"
+            | _ -> "th" in
+        let months_str = ["January"; "February"; "March"; "April"; "May";
+            "June"; "July"; "August"; "September"; "October"; "November";
+            "December"] in
+        let month_str = List.nth months_str (month - 1) in
+        Printf.sprintf "%s %d%s, %4d" month_str day (getDayPostfix day) year
+;;
+
+(* Test the date2str function with a few common and exceptional cases *)
+let test_date2str d m y expect =
+    let str = (date2str d m y) in
+    Printf.printf "%d %d %d -> %s, (should be %s, yields %s)\n"
+        d m y (if str = expect then "success" else "failure") expect str
+;;
+
+test_date2str 1 1 2010 "January 1st, 2010";;
+test_date2str 9 2 2010 "February 9th, 2010";;
+
+(* Sum all digits of a natural number *)
+let rec sum_digits n =
+    if n < 0 then raise Exit else
+    let str = string_of_int n in
+    let l = String.length str in
+    if l = 1 then
+        int_of_string str
+    else
+        int_of_char str.[0] - 48
+            + sum_digits (int_of_string (String.sub str 1 (l - 1)))
+;;
+(* Get the digital root of a natural number n *)
+let rec digitRoot n =
+    let sum = sum_digits n in
+    if (String.length (string_of_int sum) == 1) then sum else (digitRoot sum)
+;;
+
+(* Test the digitRoot function for a few known solutions *)
+let test_digitRoot n expect =
+    let root = digitRoot n in
+    Printf.printf "%d -> %s, (should be %d, yields %d)\n"
+        n (if root = expect then "success" else "failure") expect root
+;;
+
+test_digitRoot 123 6;;
+test_digitRoot 65536 7;;
+
+(* Check if a given string is a palindrome *)
+let rec isPalindrome str =
+    let l = (String.length str) in
+    l < 2 ||
+    (str.[0] = str.[l - 1] && (isPalindrome (String.sub str 1 (l - 2))))
+;;
+
+(* Test the isPalindrome function with a few known palindromes *)
+let test_isPalindrome str expect =
+    let result = (isPalindrome str) in
+    Printf.printf "%s -> %s, (should be %b, yields %b)\n"
+        str (if result = expect then "success" else "failure") expect result
+;;
+
+test_isPalindrome "foo" false;; (* non-palindrome of odd length *)
+test_isPalindrome "foobar" false;; (* non-palindrome of even length *)
+test_isPalindrome "lepel" true;; (* palindrome of odd length *)
+test_isPalindrome "foof" true;; (* palindrome of even length *)
+test_isPalindrome "" true;; (* The empty string is a palindrome *)