package main

import (
	"fmt"
	"genstack"
)

// Test and print emptiness result.
func empty_test(s *genstack.Stack) {
	if s.Empty() {
		fmt.Println("Empty")
	} else {
		fmt.Println("Not Empty")
	}
	
}

func main() {
	var s genstack.Stack
	
	empty_test(&s)

	// Put some stuff.
	for i := 1; i < 10; i++ {
		s.Push(i)
	}
	
	empty_test(&s)

	// Lose some.
	for i := 1; i < 5; i++ {
		// Pop the item.  The data is the integer, but its declared
		// type is the interface.
		data, _ := s.Pop()

		// The odd notation is a "type assertion"  It converts the
		// type or panics if the data is not of that type (integer
		// in this case).
		fmt.Printf("%d ", data.(int))
	}
	fmt.Println()

	empty_test(&s)

	// Now, let's put some other things on.
	strings := [6]string{"there","are","some","strings","here","now"}
	d := 3.8
	for i := 0; i < len(strings); i++ {
		s.Push(strings[i])
		d = 3.487*d
		s.Push(d)
	}

	empty_test(&s)
	
	// Dump it all
	for {
		data, ok := s.Pop()
		if !ok { break }

		// This is a type switch.  As it sounds, it switches on the
		// type of a value, not a value.  The variable v has the
		// matched type inside of each case.
		switch v := data.(type) {
		case int:
			fmt.Println("Your integer, sir:", v)
		case string:
			fmt.Println("String value here:", v)
		case float64:
			fmt.Println("Float away:", v)
		default:
			fmt.Println("Don't know what kind of thingie")
		}
	}

	empty_test(&s)
}