import { Extension } from '@codemirror/state';

/**
Create an extension that enables rectangular selections. By
default, it will react to left mouse drag with the Alt key held
down. When such a selection occurs, the text within the rectangle
that was dragged over will be selected, as one selection
[range](https://codemirror.net/6/docs/ref/#state.SelectionRange) per line.
*/
declare function rectangularSelection(options?: {
    /**
    A custom predicate function, which takes a `mousedown` event and
    returns true if it should be used for rectangular selection.
    */
    eventFilter?: (event: MouseEvent) => boolean;
}): Extension;
/**
Returns an extension that turns the pointer cursor into a
crosshair when a given modifier key, defaulting to Alt, is held
down. Can serve as a visual hint that rectangular selection is
going to happen when paired with
[`rectangularSelection`](https://codemirror.net/6/docs/ref/#rectangular-selection.rectangularSelection).
*/
declare function crosshairCursor(options?: {
    key?: "Alt" | "Control" | "Shift" | "Meta";
}): Extension;

export { crosshairCursor, rectangularSelection };