code: function (name) {
      var filters = ltl.filters
      var filter = filters[name]
      if (!filter) {
        try {
          filter = filters[name] = ltl.scope[name] || (typeof require !== 'undefined' ? require(name) : null)
        } catch (ignore) {
        }
      }
      if (!filter) {
        var todo = 'Set window.ltl.filters.' + name + ' to function that accepts a state object and returns a string of HTML.'
        todo += 'Or run the following:\n  cd ' + process.cwd() + '\n  npm install --save ' + name
        throw new Error('[Ltl] Unknown filter: "' + name + '". ' + todo)
      }
      return filter
    }
docs: Get a module for filtering.