Filtering Collections
All Scala topics∙ Scala
Learn Filtering Collections in Scala with clear explanations and practical examples.
Syntax
object Main extends App {
println("Hello Scala")
}
Example
val nums = List(1,2,3)
val doubled = nums.map(_ * 2)
println(doubled)
Expected Output
Filtering CollectionsReal-World Uses
- 1Scala is used for JVM backends and big-data tooling (notably Apache Spark).
Common Mistakes
- 1Overusing complex abstractions early instead of keeping code simple.
Best Practices
- 1Prefer immutability with `val` and pure functions where possible.
- 2Use pattern matching for clear control flow.
- 3Choose the right collection and avoid unnecessary conversions.
Key points
- 1Prefer immutability with `val` when possible.
- 2Pattern matching helps express logic clearly.
- 3Choose the right collection and keep transformations readable.
Quick Summary
- Scala combines functional and object-oriented programming on the JVM.
- Immutability and pattern matching are core strengths.
- Practice by editing the example and observing output.
Interview Questions
Q1. What is the difference between `val` and `var` in Scala?
Answer: `val` is immutable; `var` is mutable.
Q2. What is pattern matching used for?
Answer: Decomposing values and implementing branching logic in a concise way.
Quiz
Which keyword defines an immutable value in Scala?