Cell dependency graph

A Directed Acyclic Graph is used to store cells and its dependencies.

Installation

This package is required by calculator.

yarn add @rowsncolumns/dag

Usage

import { CellCoordinate, Dag } from "@rowsncolumns/dag";

const dag = new Dag()

// Consider user enters a formula in B1
// B1 = A1 + 10
const A1 = { rowIndex: 1, columnIndex: 1, sheetId: 1}
const B1 = { rowIndex: 2, columnIndex: 1, sheetId: 1}

dag.addNodeInput(B1, A1)
dag.markCellAsDirty(B1)

// Returns B1 as a cell to calculate
const dirtyCells = dag.getDirtyNodes()

// Now user changes A1
dag.markCellAsDirty(A1)

// Returns B1 as a cell to calculate
const dirtyCells = dag.getDirtyNodes()

Exporting DAG as JSON

import { CellCoordinate, Dag } from "@rowsncolumns/dag";

const dag = new Dag()

// Export to JSON and persist it in server
const json = dag.toJSON()

// Restore from json
dag.fromJSON(json)