Start Scripting:Verb Actions

Verb actions provide a hook for authors to inject custom code into the doTry and doSuccess phases of a verb. Verb actions can be used to augment or override a verb's built-in logic. Action calls are made from within built-in blocks of code. Usually, actions are placed as close as possible to the top of a block, so that an author can override the entire block if they choose. Sometimes, actions may fall a little lower in the block; for example, if the verb needs to resolve some issue involving the order of words in the input before moving on to processing the nouns. This is just a mild warning to note that verb actions may not be perfectly consistent from verb to verb.

Here's an example of how you might hook an asset into a verb action. In this example, onTryThrowThis, onTryThrowThisAtThat, onThrowThis and onThrowThisAtThat are all actions of throw. You can find each verb's actions listed on its doc page.

MyGame.createAsset({
  class: "NPC",
  name: "cave troll",
  place: {in: "cave"},
});

MyGame.createAsset({
  class: "Weapon",
  name: "throwing star",
  dov: { 
    throw: { 
      // this lets a player throw the star at anything
      with_anything: true, 
    }, 
  }, 
  descriptions: {
    look: "It's a little star of black metal with sharpened points. ",

    // descriptions.throw is one way to print a string when the asset is thrown
    // If you also use verb actions as shown below, 
    // you may find the output competes with itself.
    // You can choose which option works the best for you.
    throw: "It bounces across the floor with a series of metallic clangs. ",
  },
  article: "the",
  place: { in: "weapons rack" },
  onTryThrowThis: function(params)
  {
    // this results if the player tries to throw the star
    // it will print independently of any other output the verb prints
    let msg = "You limber up your arm for a good overhand throw. ";
    MyGame.print(msg);
  },
  onTryThrowThisAtThat: 
  { 
    "cave troll": function(params)
    {
      // this results only if the player tries to throw the star at the troll
      let msg = "You size up the troll and ready your arm for a strong throw. ";
      MyGame.print(msg);
    }
  },
  onThrowThis: function(params)
  {
    // this results if the player succeeds in throwing the star
    let msg = "You feel a painful twinge in your arm after releasing the star. ";
    MyGame.print(msg);
  },
  onThrowThisAtThat: 
  { 
    "cave troll": function(params)
    {
      // this results only if the player succeeds in throwing the star at the troll
      let msg = "The star thuds to a stop in the troll's chest. The troll looks annoyed. ";
      MyGame.print(msg);
    }
  }
});