Data commit

Task/Queue-Definition/Picat/queue-definition-1.picat

@@ -0,0 +1,49 @@
+go =>
+  println("Test 1"),
+  queue_test1,
+  nl.
+
+empty(Q) => Q = [].
+push(Queue, Value) = Q2 =>
+  Q2 = [Value] ++ Queue.
+pop(Q,_) = _, Q==[] ; var(Q) =>
+   throw $error(empty_queue,pop,'Q'=Q).
+pop(Queue,Q2) = Queue.last() =>
+   Q2 = [Queue[I] : I in 1..Queue.len-1].
+
+queue_test1 =>
+
+    % create an empty queue
+    println("Start test 2"),
+    empty(Q0),
+    printf("Create queue %w%n%n", Q0),
+
+    % add numbers 1 and 2
+    println("Add numbers 1 and 2 : "),
+    Q1 = Q0.push(1),
+    Q2 = Q1.push(2),
+
+    % display queue
+    printf("Q2: %w\n\n", Q2),
+
+    % pop element
+    V = Q2.pop(Q3),
+
+    % display results
+    printf("Pop : Value: %w Queue: %w\n\n", V, Q3),
+
+    % test the queue
+    print("Test of the queue: "),
+    ( Q3.empty() -> println("Queue empty"); println("Queue not empty") ),
+    nl,
+
+    % pop the elements
+    print("Pop the queue : "),
+    V1 = Q3.pop(Q4),
+    printf("Value %w Queue : %w%n%n", V1, Q4),
+
+    println("Pop empty queue:"),
+    catch(_V = Q4.pop(_Q5),Exception,println(Exception)),
+    nl,
+
+    println("\nEnd of tests.").

Task/Queue-Definition/Picat/queue-definition-2.picat

@@ -0,0 +1,51 @@
+go2 =>
+  println("Test 2"),
+  queue_test2,
+  nl.
+
+empty2() = [].
+push2(Queue, Value) = Q2 =>
+  Q2 = [Value] ++ Queue.
+pop2(Q,_) = _, Q==[] ; var(Q) =>
+   throw $error(empty_queue,pop,'Q'=Q).
+pop2(Queue,V) = [Queue[I] : I in 1..Queue.len-1] =>
+   V = Queue.last().
+
+queue_test2 =>
+    % create an empty queue
+    Q = empty2(),
+    printf("Create queue %w%n%n", Q),
+
+    % add numbers 1 and 2
+    println("Add numbers 1 and 2 : "),
+    Q := Q.push2(1).push2(2),
+
+    % display queue
+    printf("Q: %w\n\n", Q),
+
+    % pop element
+    Q := Q.pop2(V),
+
+    % display results
+    printf("Pop : Value: %w Queue: %w\n\n", V, Q),
+
+    % test the queue
+    print("Test of the queue: "),
+    ( Q.empty() -> println("Queue empty"); println("Queue not empty") ),
+    nl,
+
+    % pop the elements
+    print("Pop the queue : "),
+    Q := Q.pop2(V2),
+    printf("Value %w Queue : %w%n%n", V2, Q),
+
+    println("Pop empty queue:"),
+    catch(_ = Q.pop2(_V),Exception,println(Exception)),
+
+    % command chaining
+    println("\nCommand chaining: "),
+    Q := Q.push2(3).push2(4),
+    Q := Q.pop2(V3).pop2(V4),
+    printf("V3: %w V4: %w\n", V3, V4),
+    nl,
+    println(q=Q).