message: improve editor model documentation
diff: @@ -19,6 +19,13 @@ import {diffAtCaret, diffDeletion} from "./diff";
  import DocumentPosition from "./position";
  import Range from "./range";
  +/**
  + * @callback ModelCallback
  + * @param {DocumentPosition?} caretPosition the position where the caret should be position
  + * @param {string?} inputType the inputType of the DOM input event
  + * @param {object?} diff an object with `removed` and `added` strings
  + */
  +
  /**
  * @callback TransformCallback
  * @param {DocumentPosition?} caretPosition the position where the caret should be position
  @@ -50,6 +57,9 @@ export default class EditorModel {
  this._transformCallback = transformCallback;
  }
  + /** Set a callback for rerendering the model after it has been updated.
  + * @param {ModelCallback} updateCallback
  + */
  setUpdateCallback(updateCallback) {
  this._updateCallback = updateCallback;
  }
  @@ -376,6 +386,11 @@ export default class EditorModel {
  return new DocumentPosition(index, totalOffset - currentOffset);
  }
  + /**
  + * Starts a range, which can span across multiple parts, to find and replace text.
  + * @param {DocumentPosition} position where to start the range
  + * @return {Range}
  + */
  startRange(position) {
  return new Range(this, position);
  }
  