Improve documentation (#27)

README.md

@@ -11,9 +11,66 @@ Interactive prompt for command-line applications.
 [![Go Report Card](https://goreportcard.com/badge/github.com/manifoldco/promptui)](https://goreportcard.com/report/github.com/manifoldco/promptui)
 [![License](https://img.shields.io/badge/license-BSD-blue.svg)](./LICENSE.md)
 
-## Usage
+## Overview
 
-### Selection
+![promptui](https://media.giphy.com/media/xUNda0Ngb5qsogLsBi/giphy.gif)
+
+Promptui is a library providing a simple interface to create command-line
+prompts for go. It can be easily integrated into
+[spf13/cobra](https://github.com/spf13/cobra),
+[urfave/cli](https://github.com/urfave/cli) or any cli go application.
+
+Promptui has two main input modes:
+
+- `Prompt` provides a single line for user input. Prompt supports
+  optional live validation, confirmation and masking the input.
+
+- `Select` provides a list of options to choose from. Select supports
+  pagination, search, detailed view and custom templates.
+
+For a full list of options check [GoDoc](https://godoc.org/github.com/manifoldco/promptui).
+
+## Basic Usage
+
+### Prompt
+
+```go
+package main
+
+import (
+	"errors"
+	"fmt"
+	"strconv"
+
+	"github.com/manifoldco/promptui"
+)
+
+func main() {
+	validate := func(input string) error {
+		_, err := strconv.ParseFloat(input, 64)
+		if err != nil {
+			return errors.New("Invalid number")
+		}
+		return nil
+	}
+
+	prompt := promptui.Prompt{
+		Label:    "Number",
+		Validate: validate,
+	}
+
+	result, err := prompt.Run()
+
+	if err != nil {
+		fmt.Printf("Prompt failed %v\n", err)
+		return
+	}
+
+	fmt.Printf("You choose %q\n", result)
+}
+```
+
+### Select
 
 ```go
 package main
@@ -25,11 +82,10 @@ import (
 )
 
 func main() {
-	values := []string{"Monday", "Tuesday", "Wednesday", "Thursday", "Friday"}
-
 	prompt := promptui.Select{
 		Label: "Select Day",
-		Items: values,
+		Items: []string{"Monday", "Tuesday", "Wednesday", "Thursday", "Friday",
+			"Saturday", "Sunday"},
 	}
 
 	_, result, err := prompt.Run()
@@ -42,3 +98,7 @@ func main() {
 	fmt.Printf("You choose %q\n", result)
 }
 ```
+
+### More Examples
+
+See full list of [examples](https://github.com/manifoldco/promptui/tree/master/_examples)

_examples/custom_select/main.go

@@ -62,5 +62,5 @@ func main() {
 		return
 	}
 
-	fmt.Printf("You choose number %d: %+v\n", i+1, peppers[i])
+	fmt.Printf("You choose number %d: %s\n", i+1, peppers[i].Name)
 }

_examples/prompt/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"strconv"
 
@@ -10,7 +11,10 @@ import (
 func main() {
 	validate := func(input string) error {
 		_, err := strconv.ParseFloat(input, 64)
-		return err
+		if err != nil {
+			return errors.New("Invalid number")
+		}
+		return nil
 	}
 
 	prompt := promptui.Prompt{

_examples/select/main.go

@@ -7,11 +7,10 @@ import (
 )
 
 func main() {
-	values := []string{"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"}
-
 	prompt := promptui.Select{
-		Label: "Select Number",
-		Items: values,
+		Label: "Select Day",
+		Items: []string{"Monday", "Tuesday", "Wednesday", "Thursday", "Friday",
+			"Saturday", "Sunday"},
 	}
 
 	_, result, err := prompt.Run()
@@ -21,5 +20,5 @@ func main() {
 		return
 	}
 
-	fmt.Printf("You choose %s\n", result)
+	fmt.Printf("You choose %q\n", result)
 }