Sentencer

sentencer is a node.js module for madlibs-style sentence templating. It is a simple templating engine that accepts strings with actions embedded in them:

"This is {{ an_adjective }} sentence."

Where each action returns a random string selected from a list:

"This is a bankrupt sentence."

Think of it as madlibs for Javascript. Want to roll your own lorem ipsum generator? Sentencer allows you to write the structure of your sentences and plug in any kind of vocabulary you choose.

Sentencer was written for and powers Metaphorpsum. The noun and adjective lists come from a relatively small curated selection of Ashley Bovan's excellent Word Lists for Writers.

How

npm install sentencer --save

var Sentencer = require('sentencer');
 
Sentencer.make("This sentence has {{ a_noun }} and {{ an_adjective }} {{ noun }} in it.");
// returns something like "This sentence has a bat and a finless cinema in it."

Here are all of the options, described in detail below.

var Sentencer = require('sentencer');
 
Sentencer.configure({
  // the list of nouns to use. Sentencer provides its own if you don't have one!
  nounList: [],
 
  // the list of adjectives to use. Again, Sentencer comes with one!
  adjectiveList: [],
 
  // additional actions for the template engine to use.
  // you can also redefine the preset actions here if you need to.
  // See the "Add your own actions" section below.
  actions: {
    my_action: function(){
      return "something";
    }
  }
});

Actions

Sentencer works by recognizing "actions" within {{ double_brackets }}. It replaces these actions with strings. The default actions are {{ noun }}, {{ a_noun }}, {{ nouns }}, {{ adjective }}, and {{ an_adjective }}, but you can extend Sentencer to include any kind of actions you need!

The default actions will continue to work if you pass in new a nounList and/or adjectiveList using Sentencer.configure.

Sentencer's actions are written semantically so that your sentence template still reads as a sentence. While this was simply a design decision, it does make templates easier to read and you are encouraged to follow this format if you create custom actions.

"{{ noun }}"

Returns a random noun from the noun list.

var noun = Sentencer.make("{{ noun }}")
// "actor", "knight", "orchid", "pizza", etc.

"{{ a_noun }}"

Returns a random noun from the noun list with "a" or "an" in front of it.

var nounWithArticle = Sentencer.make("{{ a_noun }}")
// "an actor", "a knight", "an orchid", "a pizza", etc.

"{{ nouns }}"

Returns the pluralized form of a random noun from the noun list. It's not 100% perfect, but it's probably 97% perfect.

var pluralNoun = Sentencer.make("{{ nouns }}")
// "actors", "knights", "orchids", "pizzas", etc.

"{{ adjective }}"

Returns a random adjective from the adjective list.

var adjective = Sentencer.make("{{ adjective }}")
// "blending", "earthy", "rugged", "untamed", etc.

"{{ an_adjective }}"

Returns a random adjective from the adjective list with "a" or "an" in front of it.

var adjective = Sentencer.make("{{ an_adjective }}")
// "a blending", "an earthy", "a rugged", "an untamed", etc.

Add your own actions

When configuring Sentencer you can provide your own "actions", which are just functions that return something. The name of the function that you pass into actions is how you will reference it within a sentence template.

Here's an example of an action that returns a random number from 1 to 10.

var Sentencer = require('sentencer');
 
Sentencer.configure({
  actions: {
    number: function() {
      return Math.floor( Math.random() * 10 ) + 1;
    }
  }
});
 
console.log( Sentencer.make("I can count to {{ number }}.")
// "I can count to 5."

Actions can take arguments

You can pass arguments into your actions. We can use this to make a smarter version of the random number generator above...

var Sentencer = require('sentencer');
 
Sentencer.configure({
  actions: {
    number: function(min, max) {
      return Math.floor( Math.random() * (max - min) ) + min;
    }
  }
});
 
console.log( Sentencer.make("I can count to {{ number(8, 10) }}.")
// "I can count to 8."

A technical note: if Sentencer finds that you have provided arguments to your action it will use eval in order to call it. It will try/catch this in case it fails, but one definite limitation is that your action can't contain characters that would force you to use object["property"] notation. For example, "{{ my-custom-action(3) }}" would fail, whereas "{{ my_custom_action(3) }}" would succeed.

Where are the verbs?

Verb pluralization, singularization, and tense modification are difficult computer science problems. Sentencer doesn't aim to solve those problems, however present tense verb pluralization/singularization is an experimental feature of natural and could be integrated if necessary.

Sentencer was created and is maintained by Kyle Stetz. The original prototype came out of Metaphorpsum but has been rewritten from the ground up.