A Heroku-like name generator in Scala

I use a lot temporary directories at work; unfortunately I end up with headaches when I’ve spent my whole day browsing these directories which looks like SHA-1 hash keys. I love developing for the Heroku platform in my spare time, and I think one of the coolest thing is their application random naming feature. If you don’t name your application at creation time, then Heroku will randomly pick a name for you. It looks like an haiku; an evoking image of the natural world. That name is unique, human-friendly, and definitely cool!

A few examples:

  • delicate-spectrum-1819
  • late-equinox-7634
  • snowy-sea-8407
  • strong-drake-4157
  • silent-cloud-2920
  • divine-dream-2340
  • fluffy-mountain-2939
  • green-cedar-3646
  • winter-night-9260
  • powerful-equinox-8694

The following Scala lines return a Heroku-like name like the ones above; feel free to use this anywhere you need random and human-friendly tokens.

import scala.util.Random.nextInt

// full dictionaries at https://github.com/bmarcot/haiku
val adjs = List("autumn", "hidden", "bitter", "misty", "silent",
  "reckless", "daunting", "short", "rising", "strong", "timber", "tumbling",
  "silver", "dusty", "celestial", "cosmic", "crescent", "double", "far",
  "terrestrial", "huge", "deep", "epic", "titanic", "mighty", "powerful")

val nouns = List("waterfall", "river", "breeze", "moon", "rain",
  "wind", "sea", "morning", "snow", "lake", "sunset", "pine", "shadow", "leaf",
  "sequoia", "cedar", "wrath", "blessing", "spirit", "nova", "storm", "burst",
  "giant", "elemental", "throne", "game", "weed", "stone", "apogee", "bang")

def getRandElt[A](xs: List[A]): A = xs.apply(nextInt(xs.size))

def getRandNumber(ra: Range): String = {
  (ra.head + nextInt(ra.end - ra.head)).toString

def haiku: String = {
  val xs = getRandNumber(1000 to 9999) :: List(nouns, adjs).map(getRandElt)


You may want to check out the GitHub project instead. It comes with a richer dictionary with more adjectives and words. There are also useful functions to check the uniqueness of words into the dictionary, should you want to add your own ones.


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