Data commit

Task/Queue-Definition/Groovy/queue-definition-1.groovy

@@ -0,0 +1,22 @@
+class Queue {
+    private List buffer
+
+    public Queue(List buffer =  new LinkedList()) {
+        assert buffer != null
+        assert buffer.empty
+        this.buffer = buffer
+    }
+
+    def push (def item) { buffer << item }
+    final enqueue = this.&push
+
+    def pop() {
+        if (this.empty) throw new NoSuchElementException('Empty Queue')
+        buffer.remove(0)
+    }
+    final dequeue = this.&pop
+
+    def getEmpty() { buffer.empty }
+
+    String toString() { "Queue:${buffer}" }
+}

Task/Queue-Definition/Groovy/queue-definition-2.groovy

@@ -0,0 +1,27 @@
+def q = new Queue()
+assert q.empty
+
+['Crosby', 'Stills'].each { q.push(it) }
+assert !q.empty
+['Nash', 'Young'].each { q.enqueue(it) }
+println q
+assert !q.empty
+assert q.pop() == 'Crosby'
+println q
+assert !q.empty
+assert q.dequeue() == 'Stills'
+println q
+assert !q.empty
+assert q.pop() == 'Nash'
+println q
+assert !q.empty
+q.push('Crazy Horse')
+println q
+assert q.dequeue() == 'Young'
+println q
+assert !q.empty
+assert q.pop() == 'Crazy Horse'
+println q
+assert q.empty
+try { q.pop() } catch (NoSuchElementException e) { println e }
+try { q.dequeue() } catch (NoSuchElementException e) { println e }