undo-stack

A simple undo/redo library with optional undo chunking (batch undos) and a pluggable logger with nice output for your viewing pleasure.

EXAMPLE

var History = require('undo-stack');

var history = new History({
    logger: console.log,
    limit: 200
});

var x = 5;

// To add a history step
history.add({
    name: 'plus 3',
    redo: function () { x += 3; },
    undo: function () { x -= 3; }
}); // x is still 5

// To add and call use .do()
// shortcut for .add(stackStepObj, true)
history.do({
    name: 'call on add',
    redo: function () { x += 3; },
    undo: function () { x -= 3; }
}); // x is 8 now

history
    .undo() // x is 5
    .redo(); // x is 8 again

// Chunks
history.startChunk('plus 7')
    .do({
        name: 'plus 2',
        redo: function () {x += 2;},
        undo: function () {x -= 2;}
    }) // x is 10
    .do({
        name: 'plus 5',
        redo: function () {x += 5;},
        undo: function () {x -= 5;}
    }) // x is 15
    .endChunk();

history
    .undo() // x is 8
    .redo(); // x is 15 again

LICENSE

MIT