Add syntax check fn q

src/exam01/question5.sml

@@ -0,0 +1,31 @@
+fun q4 _ ([], []) = true
+  | q4 _ ([], x::xs) = false
+  | q4 _ (x::xs, []) = false
+  | q4 f (x::xs,y::ys) = y = (f x) andalso q4 f (xs, ys);
+
+
+(* Question 4a
+   My answer: true
+   Correct answer: error, because cannot do equality check on reals
+*)
+(* q4 (fn x => x + 1.0) ([1.1,2.2,3.3], [2.1,3.2,4.3]);  *)
+
+(* Question 4b
+   My answer: true
+   Correct answer: error, because the operand should be a tuple of 
+                   two lists and this is currying with 2 arguments. 
+                   I.e., should be q4 floor ([1.1,2.2,3.3], [1,2,3])
+*)
+(* q4 floor [1.1,2.2,3.3] [1,2,3]; *)
+
+(* Question 4c
+   My answer: false
+   Correct answer: false, because of simple arithmetic reasons
+*)
+q4 (fn x => x*x) ([1,2,3],[1,4,9,16]);
+
+(* Question 4d
+   My answer: Error because tries to perform an equality operation between int list and int but equality operator requires two arguments of the same type.
+   Correct answer: true
+*)
+q4 (hd) ([[1,2], [2,3,4], [3,4,5,6,7]],[1,2,3]);