Reviewed by Aditya Kumar · Last reviewed 2026-03-24
Monad: Type wrapping a computation with flatMap; obeys left/right identity and associativity. Option encapsulates optional values—Some(x) or None; handles null safely. Example: val r = for { a <- Some(1); b <- Some(2) } yield a+b. WHY: Composable error handling; avoids...
Monad: Type wrapping a computation with flatMap; obeys left/right identity and associativity. Option encapsulates optional values—Some(x) or None; handles null safely. Example: val r = for { a <- Some(1); b <- Some(2) } yield a+b. WHY: Composable error handling; avoids NullPointerException; chains transformations cleanly. SCALABILITY: Monadic composition scales in complexity; for-comprehensions improve readability. COST: Slight overhead vs. raw null checks; benefits in large codebases. Other monads: Try (exceptions), Either (typed errors), Future (async).
Red Flag: Definition without laws or composition. Pro-Move: 'We use Option for optional fields; Either for validation with typed errors; chain with flatMap in pipelines.'
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