## Release history

See [the changelog](changelog.md) for detailed release history.

## What is this?

prompt-base is a node.js library for creating command line prompts. You can use prompt-base directly for simple input prompts, or as a "base" for creating [custom prompts](#in-the-wild):

## Usage

See the [examples folder](./examples) for additional usage examples.

```js
var Prompt = require('{%= name %}');
var prompt = new Prompt({
  name: 'color',
  message: 'What is your favorite color?'
});

// promise
prompt.run()
  .then(function(answer) {
    console.log(answer);
    //=> 'blue'
  })

// or async
prompt.ask(function(answer) {
  console.log(answer);
  //=> 'blue'
});
```

You can also pass a string directly to the main export:

```js
var prompt = require('{%= name %}')('What is your favorite color?');
  
prompt.run()
  .then(function(answer) {
    console.log(answer);
  })
```


## Custom prompts

**Inherit**

```js
var Prompt = require('{%= name %}');

function CustomPrompt(/*question, answers, rl*/) {
  Prompt.apply(this, arguments);
}

Prompt.extend(CustomPrompt);
```

## API
{%= apidocs("index.js") %}

## Events

### prompt

Emitted when a prompt (plugin) is instantiated, _after the readline interface is created, but before the actual "question" is asked_.

**Example usage**

```js
enquirer.on('prompt', function(prompt) {
  // do stuff with "prompt" instance
});
```

### ask

Emitted when the actual "question" is asked.

**Example usage**

Emit `keypress` events to supply the answer (and potentially skip the prompt if the answer is valid):

```js
enquirer.on('ask', function(prompt) {
  prompt.rl.input.emit('keypress', 'foo');
  prompt.rl.input.emit('keypress', '\n');
});
```

Change the prompt message:

```js
enquirer.on('ask', function(prompt) {
  prompt.message = 'I..\'m Ron Burgundy...?';
});
```

### answer

Emitted when the final (valid) answer is submitted, and custom validation function (if defined) returns true.

_(An "answer" is the final input value that's captured when the `readline` emits a `line` event; e.g. when the user hits `enter`)_

**Example usage**

```js
enquirer.on('answer', function(answer) {
  // do stuff with answer
});
```

## In the wild

The following custom prompts were created using this library:

{%= related(verb.related.prompts) %}

[rl]: https://nodejs.org/api/readline.html#readline_rl_write_data_key
[resume]: https://nodejs.org/api/readline.html#readline_rl_resume