@suntech-innovation/option

A TypeScript implementation of Rust's Option<T> type for safe handling of nullable values with functional programming patterns. Eliminates common null/undefined runtime errors by wrapping potentially null values in an Option container that must be explicitly handled.

Features

• Null Safety: Eliminates null/undefined runtime errors through explicit handling
• Rust-inspired API: Familiar patterns with methods like unwrap(), map(), and_then()
• Functional Programming: Support for method chaining and functional composition
• Type-safe JSON Parsing: Schema validation returning Options instead of throwing errors
• Performance Optimized: Minimal overhead, tree-shakeable, no side effects
• Chart/Data Processing: Specialized utilities for safe array operations and data extraction

Installation

npm install @suntech-innovation/option

Quick Start

import { Option, Some, None, OptionUtils } from '@suntech-innovation/option';

// Create Options
const someValue = Some(42);
const noValue = None();

// Safe array operations
const first = OptionUtils.head([1, 2, 3]); // Some(1)
const empty = OptionUtils.head([]); // None()

// Chain operations safely
const result = first
  .map(x => x * 2)
  .filter(x => x > 0)
  .unwrap_or(0); // 2

Core API

Option Methods

• State: is_some(), is_none()
• Extraction: unwrap(), expect(), unwrap_or(), unwrap_or_else()
• Transform: map(), and_then(), filter()
• Combine: or(), or_else(), and(), xor()

OptionUtils

• Array ops: head(), last(), at()
• Safe execution: tryCatch()
• Combinators: all(), firstSome()

JSON Parser

Type-safe JSON parsing with schema validation:

import { JsonParser } from '@suntech-innovation/option';

const parser = new JsonParser();
const schema = {
  name: parser.string,
  age: parser.number,
  email: parser.optional(parser.string)
};

const result = parser.parseObject(jsonString, schema);
// Returns Option<{name: string, age: number, email?: string}>

Documentation

• Complete API Guide
• JSON Parser Documentation

Build

Run ng build option to build the project. The build artifacts will be stored in the dist/ directory.

Publishing

After building your library with ng build option, go to the dist folder cd dist/option and run npm publish.

Running unit tests

Run ng test option to execute the unit tests via Karma.