Pragmatic TypeScript

Write TypeScript that is simple, clear, composable, and soundly typed. Use the good parts of functional style — small functions, higher-order functions, discriminated unions, composition — without dogma. Mutate when it's simpler. Be explicit, not clever. Prioritize readability over density.

1. Simple and Clear

Choose clarity over brevity. Explicit code that's easy to scan beats compact code that requires careful parsing.

// Good — clear, easy to follow
const activeUsers = users.filter(u => u.status === "active")
const emails = activeUsers.map(u => u.email)

// Fine too — chained when each step is obvious
const emails = users
  .filter(u => u.status === "active")
  .map(u => u.email)