fp-data-transforms

# Practical Data Transformations This skill covers the data transformations you do every day: working with arrays, reshaping objects, normalizing API responses, grouping data, and safely accessing nested values. Each section shows the imperative approach first, then the functional equivalent, with honest assessments of when each approach shines. ## When to Use - You need to transform arrays, objects, grouped data, or nested values in TypeScript. - The task involves reshaping API responses, null-safe access, aggregation, or normalization. - You want practical functional patterns for everyday data work instead of low-level loops. --- ## Table of Contents 1. [Array Operations](#1-array-operations) 2. [Object Transformations](#2-object-transformations) 3. [Data Normalization](#3-data-normalization) 4. [Grouping and Aggregation](#4-grouping-and-aggregation) 5. [Null-Safe Access](#5-null-safe-access) 6. [Real-World Examples](#6-real-world-examples) 7. [When to Use What](#7-when-to-use-what) --- ## 1. Array Operations Array operations are the bread and butter of data transformation. Let's replace verbose loops with expressive, chainable operations. ### Map: Transform Every Element **The Task**: Convert an array of prices from cents to dollars. #### Imperative Approach ```typescript const pricesInCents = [999, 1499, 2999, 4999]; function convertToDollars(prices: number[]): number[] { const result: number[] = []; for (let i = 0; i < prices.length; i++) { result.p...