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LetsGit.IT/Categories/TypeScript
TypeScriptmedium

What is tsconfig.json and what does strictNullChecks do?

Tags
#tsconfig#null
Back to categoryPractice quiz

Answer

tsconfig.json configures the TypeScript compiler. strictNullChecks treats null/undefined as distinct types and prevents using them where a value is required.

Advanced answer

Deep dive

Expanding on the short answer — what usually matters in practice:

  • Context (tags): tsconfig, null
  • Explain the "why", not just the "what" (intuition + consequences).
  • Trade-offs: what you gain/lose (time, memory, complexity, risk).
  • Edge cases: empty inputs, large inputs, invalid inputs, concurrency.

Examples

A tiny example (an explanation template):

// Example: discuss trade-offs for "what-is-tsconfig.json-and-what-does-strictnullch"
function explain() {
  // Start from the core idea:
  // tsconfig.json configures the TypeScript compiler. strictNullChecks treats null/undefined a
}

Common pitfalls

  • Too generic: no concrete trade-offs or examples.
  • Mixing average-case and worst-case (e.g., complexity).
  • Ignoring constraints: memory, concurrency, network/disk costs.

Interview follow-ups

  • When would you choose an alternative and why?
  • What production issues show up and how do you diagnose them?
  • How would you test edge cases?

Related questions

JavaScript
Explain null vs undefined in JavaScript.
#types#null#undefined
Databases
SQL NULL: why is `col = NULL` not true and what should you use?
#sql#null#three-valued-logic