Update simple example to use new Model interface-based structure

examples/simple/main.go

@@ -11,18 +11,9 @@ import (
 	tea "github.com/charmbracelet/bubbletea"
 )
 
-// A model can be more or less any type of data. It holds all the data for a
-// program, so often it's a struct. For this simple example, however, all
-// we'll need is a simple integer.
-type model int
-
-// Messages are events that we respond to in our Update function. This
-// particular one indicates that the timer has ticked.
-type tickMsg time.Time
-
 func main() {
 	// Log to a file. Useful in debugging. Not required.
-	logfilePath := os.Getenv("TEA_LOG")
+	logfilePath := os.Getenv("BUBBLETEA_LOG")
 	if logfilePath != "" {
 		if _, err := tea.LogToFile(logfilePath, "simple"); err != nil {
 			log.Fatal(err)
@@ -30,23 +21,30 @@ func main() {
 	}
 
 	// Initialize our program
-	p := tea.NewProgram(initialize, update, view)
+	p := tea.NewProgram(model(5))
 	if err := p.Start(); err != nil {
 		log.Fatal(err)
 	}
 }
 
-func initialize() (tea.Model, tea.Cmd) {
-	return model(5), tick
+// Messages are events that we respond to in our Update function. This
+// particular one indicates that the timer has ticked.
+type tickMsg time.Time
+
+// A model can be more or less any type of data. It holds all the data for a
+// program, so often it's a struct. For this simple example, however, all
+// we'll need is a simple integer.
+type model int
+
+func (m model) Init() tea.Cmd {
+	return tick
 }
 
 // Update is called when messages are recived. The idea is that you inspect
 // the message and update the model (or send back a new one) accordingly. You
 // can also return a commmand, which is a function that peforms I/O and
 // returns a message.
-func update(msg tea.Msg, mdl tea.Model) (tea.Model, tea.Cmd) {
-	m, _ := mdl.(model)
-
+func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	switch msg.(type) {
 	case tea.KeyMsg:
 		return m, tea.Quit
@@ -62,8 +60,7 @@ func update(msg tea.Msg, mdl tea.Model) (tea.Model, tea.Cmd) {
 
 // Views take data from the model and return a string which will be rendered
 // to the terminal.
-func view(mdl tea.Model) string {
-	m, _ := mdl.(model)
+func (m model) View() string {
 	return fmt.Sprintf("Hi. This program will exit in %d seconds. To quit sooner press any key.\n", m)
 }