Awesome

malarkey

Simulate a typewriter effect in vanilla JavaScript.

• Flexible API allowing granular control
• Option to repeat the sequence indefinitely
• Allows stopping and resuming the sequence on-the-fly
• 524 bytes gzipped

Usage

Editable demo (CodePen)

<div class="typewriter"></div>

const malarkey = require('malarkey')

const element = document.querySelector('.typewriter')
function callback (text) {
  element.textContent = text
}
const options = {
  typeSpeed: 50,
  deleteSpeed: 50,
  pauseDuration: 2000,
  repeat: true
}
malarkey(callback, options)
  .type('Say hello')
  .pause()
  .delete()
  .type('Wave goodbye')
  .pause()
  .delete()

API

const malarkey = require('malarkey')

const m = malarkey(callback [, options])

Initialise the typewriter effect with the given optional options settings.

• callback is a function that is invoked for every type and delete event in the sequence. The function signature is (text), where text is the string of characters that have been typed so far.

• options is an object literal:

  Key	Description	Default
  typeSpeed	Duration in milliseconds to type a single character	50
  deleteSpeed	Duration in milliseconds to delete a single character	50
  pauseDuration	Duration in milliseconds to pause	2000
  repeat	Whether to repeat the entire sequence indefinitely	false

m.type(string [, options])

Type the given string, one character at a time.

• Set options.speed to override the default typeSpeed.

m.delete([characterCount, options])

Delete the specified number of characters, one character at a time.

• characterCount is a positive integer. If not specified, all characters previously typed will be deleted, one character at a time.
• Set options.speed to override the default deleteSpeed.

m.pause([options])

Do nothing for some duration.

• Set options.duration to override the default pauseDuration.

m.clear()

Immediately clear all characters that were typed.

m.call(fn)

Call the given fn function.

• The function signature of fn is (callback, text). Invoke callback to signal that fn has finished execution and that we can move on to the next event in the sequence.

m.triggerStop([fn])

Stops the sequence. Calls the given fn function when the sequence has been stopped.

• The function signature of fn is (text).

m.triggerResume()

Resume the sequence. Has no effect if the sequence is already running.

m.isStopped()

Returns true if the sequence is currently stopped, else returns false.

Installation

Install via yarn:

$ yarn add malarkey

Or npm:

$ npm install --save malarkey

License

MIT