Fireblocks Assignment - Reactive System CLI

This CLI application implements a simple reactive system similar to a spreadsheet. It features two types of cells:

• Input Cells: Hold literal numeric values.
• Computed Cells: Hold a formula (starting with =) that references other cells using {<index>} notation. Computed cells update their values automatically when the input cells change.

Features

• Reactive Updates: Computed cells recalculate automatically when input values change.
• Interactive Console Menu: Provides options to:
  • Print the current state of all cells.
  • Change the value of a cell, triggering updates to dependent computed cells.
• Formula Evaluation: Supports basic arithmetic operations (+, -, *, /)

Installation

Prerequisites

• Node.js installed (>= 20.0.0)

Setup

1. Clone the repository:

   git clone <repository-url>
   cd fireblocks_assignment

2. Install dependencies:

   npm install

Usage

Running the Program

npm start <path-to-input-file>

Example:

npm start input.txt

Input File Format

The input file should contain a comma-separated list of cell definitions. Each cell can either be:

• A direct number (e.g., 5 or 12)
• A formula prefixed with = and referencing other cells via {index} (e.g., =2+{0})

Example input file:

2, 18, =2*{0}, 9, ={2}+1*5

Interactive Commands

Once running, the program presents a menu:

• a - Print the current state of all cells.
• b <cell index> <new value> - Change a cell's value.

Example Execution

Menu:
a. Print current state
b. Change value (usage: b <cell index> <new value>)

# a
[0: 2], [1: 18], [2: 4], [3: 9], [4: 25]

# b 0 3
Cell #0 changed to 3

# a
[0: 3], [1: 18], [2: 6], [3: 9], [4: 35]

Development

Testing

Tests are not included in the initial implementation but can be added later.