Lookup tables shorthand in javascript.

LookupTablesShorthand.js

// Longhand
if (type === 'aligator') {
  aligatorBehavior();
}
else if (type === 'parrot') {
  parrotBehavior();
}
else if (type === 'dolphin') {
  dolphinBehavior();
}
else if (type === 'bulldog') {
  bulldogBehavior();
} else {
  throw new Error('Invalid animal ' + type);
}

// Shorthand
var types = {
  aligator: aligatorBehavior,
  parrot: parrotBehavior,
  dolphin: dolphinBehavior,
  bulldog: bulldogBehavior
};
 
var func = types[type];
(!func) && throw new Error('Invalid animal ' + type); func();