Rust Pattern Matching Quiz

0 Passed

0% acceptance

40 comprehensive questions on Rust's pattern matching system, covering match expressions, destructuring, guards, wildcards, and enum matching — with 11 code examples demonstrating practical pattern matching techniques.

40 Questions

~80 minutes

Question 1

What is pattern matching in Rust and why is it important?

A way to check if a value matches certain patterns and execute code based on the match, providing compile-time exhaustiveness guarantees

A way to compare two values for equality

A replacement for if-else statements

A way to sort data structures

Question 2

What is the basic syntax of a match expression in Rust?

match value { pattern => expression, pattern => expression, ... }

switch value { case pattern: expression; case pattern: expression; ... }

if value matches pattern { expression } else if value matches pattern { expression }

match value with pattern => expression, pattern => expression, ...

Question 3

What does it mean for a match expression to be exhaustive?

Every possible value of the matched type must be covered by at least one pattern

The match must handle the most common cases first

The match must be optimized for performance

The match must use all available patterns

Question 4

What will this match expression return?

rust

fn main() {
    let number = 3;
    let result = match number {
        1 => "one",
        2 => "two",
        3 => "three",
        _ => "other",
    };
    println!("Result: {}", result);
}

Result: three

Result: other

Compilation error

Runtime error

Question 5

What is destructuring in pattern matching?

Breaking down complex data structures into their component parts during matching

Converting data types during matching

Sorting data during matching

Validating data during matching

Question 6

How do you destructure a tuple in a match expression?

Use (var1, var2, ...) => expression to bind tuple elements to variables

Use [var1, var2, ...] => expression for tuples

Use {var1, var2, ...} => expression for tuples

Tuples cannot be destructured in match

Question 7

What will this tuple destructuring code output?

rust

fn main() {
    let triple = (1, 2, 3);
    match triple {
        (0, y, z) => println!("First is 0, y = {}, z = {}", y, z),
        (1, y, z) => println!("First is 1, y = {}, z = {}", y, z),
        _ => println!("Something else"),
    }
}

First is 1, y = 2, z = 3

First is 0, y = 2, z = 3

Something else

Compilation error

Question 8

What are guards in pattern matching and how do you use them?

Additional conditions added with 'if' that must be true for a pattern to match

Security checks that prevent invalid matches

Performance optimizations for matching

Type checks for pattern matching

Question 9

How do you use a guard in a match expression?

pattern if condition => expression

pattern where condition => expression

pattern && condition => expression

Guards cannot be used in match expressions

Question 10

What will this code with a guard output?

rust

fn main() {
    let num = 4;
    match num {
        x if x % 2 == 0 => println!("Even number: {}", x),
        x if x % 2 == 1 => println!("Odd number: {}", x),
        _ => println!("Something else"),
    }
}

Even number: 4

Odd number: 4

Something else

Compilation error

Question 11

What is the underscore (_) wildcard pattern used for?

Ignoring values that you don't care about in a pattern

Matching any single character

Matching zero or more characters

Creating default cases

Question 12

When should you use the underscore pattern in match expressions?

When you want to handle all remaining cases that don't match other patterns

When you want to match specific values only

When you want to create loops

When you want to sort values

Question 13

What does the double dot (..) syntax do in patterns?

Ignores remaining fields in struct patterns or elements in tuple patterns

Creates range patterns for matching

Repeats the previous pattern

Creates nested patterns

Question 14

How do you destructure a struct in a match pattern?

Use StructName { field1, field2, .. } => expression

Use StructName(field1, field2) => expression

Use {field1, field2} => expression

Structs cannot be destructured in match

Question 15

What will this struct destructuring code do?

rust

struct Point {
    x: i32,
    y: i32,
}

fn main() {
    let p = Point { x: 10, y: 20 };
    match p {
        Point { x: 0, y: 0 } => println!("Origin"),
        Point { x, y } => println!("Point at ({}, {})", x, y),
    }
}

Print 'Point at (10, 20)'

Print 'Origin'

Compilation error

Runtime error

Question 16

What is enum matching and why is it particularly useful in Rust?

Matching on enum variants to handle different cases safely, with compile-time guarantees that all variants are covered

Converting enums to other types

Sorting enum values

Creating enum instances

Question 17

How do you match on enum variants in a match expression?

Use EnumName::Variant => expression for each variant

Use Variant => expression without the enum name

Use case EnumName::Variant: expression

Enums cannot be matched

Question 18

What will this enum matching code output?

rust

enum Message {
    Quit,
    Move { x: i32, y: i32 },
    Write(String),
    ChangeColor(i32, i32, i32),
}

fn main() {
    let msg = Message::Write(String::from("hello"));
    match msg {
        Message::Quit => println!("Quit"),
        Message::Move { x, y } => println!("Move to ({}, {})", x, y),
        Message::Write(text) => println!("Write: {}", text),
        Message::ChangeColor(r, g, b) => println!("Color: ({}, {}, {})", r, g, b),
    }
}

Write: hello

Quit

Move to (0, 0)

Compilation error

Question 19

What happens if you don't handle all enum variants in a match expression?

Compilation error: pattern is not exhaustive

Runtime error

The unhandled variants are ignored

The match returns a default value

Question 20

How do you handle multiple enum variants with the same behavior?

Use the | (or) operator: Variant1 | Variant2 => expression

Use separate arms for each variant

Use guards to combine variants

This is not possible

Question 21

What is match ergonomics in Rust?

Automatic dereferencing and borrowing adjustments in match patterns

Automatic code formatting for match expressions

Performance optimizations for match expressions

Ergonomic keyboard shortcuts for writing match code

Question 22

How do you match on references in patterns?

Use &pattern for matching references, or let match ergonomics handle it

Use *pattern for dereferencing

References cannot be matched directly

Use ref pattern for references

Question 23

What will this reference matching code do?

rust

fn main() {
    let value = Some(42);
    match &value {
        Some(v) => println!("Got {}", v),
        None => println!("Nothing"),
    }
    // value is still accessible here
    println!("Value is still: {:?}", value);
}

Print 'Got 42' then 'Value is still: Some(42)'

Compilation error

Print 'Got 42' then lose access to value

Runtime error

Question 24

What are match arms and how do they work?

Each pattern => expression pair in a match expression, executed when the pattern matches

The different branches of a match expression

Both A and B are correct

The patterns themselves

Question 25

How do you use pattern matching with if let for simpler cases?

if let pattern = value { ... } else { ... }

if value matches pattern { ... }

if pattern in value { ... }

if let is not used for pattern matching

Question 26

What is the difference between match and if let?

match requires exhaustive coverage of all cases, if let only handles one pattern

match is faster than if let

if let requires exhaustive coverage

There is no functional difference

Question 27

How do you match on ranges of values?

Use start..=end for inclusive ranges in patterns

Use start..end for exclusive ranges

Both A and B work depending on the context

Range matching is not supported

Question 28

What will this range matching code output?

rust

fn main() {
    let number = 15;
    match number {
        0..=10 => println!("Low"),
        11..=20 => println!("Medium"),
        _ => println!("High"),
    }
}

Medium

Low

High

Compilation error

Question 29

What is binding in pattern matching?

Creating variables that bind to parts of the matched value

Connecting patterns to expressions

Creating references to matched values

Binding is not a pattern matching concept

Question 30

How do you use @ bindings in patterns?

pattern @ binding_variable to bind the entire matched value to a variable while also destructuring it

binding_variable @ pattern for reverse binding

@ is not used in Rust patterns

pattern & binding_variable for reference binding

Question 31

What will this @ binding code demonstrate?

rust

fn main() {
    let msg = Some(42);
    match msg {
        value @ Some(42) => println!("Got the answer: {:?}", value),
        Some(other) => println!("Got something else: {}", other),
        None => println!("Nothing"),
    }
}

Print 'Got the answer: Some(42)'

Print 'Got something else: 42'

Compilation error

Print 'Nothing'

Question 32

What is the ref keyword used for in patterns?

Creating references to parts of the matched value instead of moving them

Referencing external variables

Creating mutable references

ref is not used in patterns

Question 33

When should you use ref in match patterns?

When you want to borrow parts of the matched value instead of moving them

When matching on references

When creating mutable bindings

ref should never be used in patterns

Question 34

What is the mut keyword used for in patterns?

Creating mutable bindings to matched parts of the value

Making the entire match mutable

Allowing mutation of the matched value

mut is not used in patterns

Question 35

How do you handle complex nested patterns in match expressions?

Use nested destructuring with appropriate syntax for each type (tuples, structs, enums)

Flatten the structure before matching

Use separate match expressions

Complex nesting is not supported

Question 36

What will this nested pattern matching do?

rust

enum Shape {
    Circle(f64),
    Rectangle(f64, f64),
}

fn main() {
    let shape = Shape::Rectangle(10.0, 20.0);
    match shape {
        Shape::Circle(radius) => println!("Circle with radius {}", radius),
        Shape::Rectangle(width, height) => println!("Rectangle {}x{}", width, height),
    }
}

Print 'Rectangle 10x20'

Print 'Circle with radius 10'

Compilation error

Runtime error

Question 37

What is the purpose of match expressions returning values?

Allowing match to be used in assignments and expressions, not just statements

Improving performance

Reducing code size

Match expressions don't return values

Question 38

How do you make match expressions more concise when many arms have the same result?

Use the | operator to combine patterns: Pattern1 | Pattern2 => result

Use multiple lines for the same arm

Use guards to combine conditions

This is not possible

Question 39

In a scenario where you're implementing a calculator that handles different operations, how would you structure the pattern matching?

Use an enum for operations and match on enum variants with destructuring for operands

Use if-else chains for each operation

Use function pointers for operations

Use a hash map of operations

Question 40

What advanced pattern matching technique would you use when you need to match a pattern but also keep a reference to the original value for later use?

Use @ bindings: pattern @ whole_value to capture both the destructured parts and the complete value

Use ref bindings to create references

Use guards with additional conditions

This requires separate matching operations

Other Quiz Categories

JavaScript

47 quizzes

Basics

Variables & Data Types

Operators & Expressions

Python

29 quizzes

Introduction & Core Fundamentals

Data Types & Zero Values

Operators & Expressions

C++

26 quizzes

Basics

Variables & Data Types

Operators & Expression

Java

22 quizzes

Java Basics & JVM Fundamentals

Variables, Data Types & Type Casting

Operators & Expressions

Matlab

21 quizzes

Basics & Environment

Variables and Data Type

Arrays and Matric

TypeScript

19 quizzes

Introduction and Overview

Installation and Configuration

Basic Types and Type Annotations

SQL Database

15 quizzes

Foundations and Basics

Basic Query Selection

Filter, Sort, and Alias Essentials

PHP

15 quizzes

Syntax Building Blocks

Node Structure and Pointer Fundamentals

Singly Linked List

QUIZZES IN Rust

Cargo and Project Setup

40 comprehensive questions on Rust's package manager Cargo, covering project initialization, building, running, project structure, and dependency management — with 15 code examples demonstrating practical Cargo usage.

Variables and Mutability

40 comprehensive questions on Rust's variable system, covering let bindings, mut keyword, shadowing, type inference, and constants — with 12 code examples demonstrating practical variable usage patterns.

Data Types

45 comprehensive questions on Rust's type system, covering scalar types, compound types, type conversions, numeric operations, and string types — with 15 code examples demonstrating practical type usage patterns.

Control Flow

45 comprehensive questions on Rust's control flow constructs, covering if expressions, loops, and control flow keywords — with 15 code examples demonstrating practical control flow usage.

Functions

40 questions covering function parameters, return values, expressions, diverging functions, and function scope in Rust.

Ownership

45 in-depth questions covering Rust's ownership system, move semantics, copy types, resource cleanup through Drop trait, precise drop timing, and ownership transfer patterns — with 12 code examples to solidify understanding.

Borrowing

45 in-depth questions covering Rust's borrowing system, immutable and mutable references, aliasing rules, reference scopes, and borrow checker validation — with 13 code examples to solidify understanding.

Lifetimes

40 in-depth questions covering Rust's lifetime system, lifetime annotations, elision rules, function signatures with lifetimes, struct references, and common lifetime errors — with 11 code examples to solidify understanding.

Strings

40 comprehensive questions on Rust's string types, covering String vs &str, UTF-8 behavior, slicing, mutating strings, and conversions — with 11 code examples demonstrating practical string handling patterns.

Collections

40 comprehensive questions on Rust's collection types, covering Vec, HashMap, VecDeque, iteration patterns, and capacity management — with 11 code examples demonstrating practical collection usage.

Slices

40 comprehensive questions on Rust's slice types, covering borrowed views, indexing, mutable slices, ranges, and slice methods — with 11 code examples demonstrating practical slice usage patterns.

Pattern Matching

Enums

40 comprehensive questions on Rust's enum system, covering simple variants, data-carrying variants, enum matching, methods on enums, and Option/Result patterns — with 11 code examples demonstrating practical enum usage.

Struct

40 comprehensive questions on Rust's struct system, covering named fields, tuple structs, methods, associated functions, and field ownership — with 11 code examples demonstrating practical struct usage.

Modules

40 comprehensive questions on Rust's module system, covering module creation, visibility, imports, paths, and the use keyword — with 11 code examples demonstrating practical module organization patterns.

Traits

40 comprehensive questions on Rust's trait system, covering trait definitions, implementations, bounds, associated types, and trait objects — with 11 code examples demonstrating practical trait usage patterns.

Generic

40 comprehensive questions on Rust's generic programming system, covering generic functions, structs, enums, impl blocks, and monomorphization — with 11 code examples demonstrating practical generic usage patterns.

Iterators

Master Rust's powerful iterator system for efficient data processing and transformation

Closures

Master Rust's closure system for capturing environment variables and creating flexible function-like constructs

Error Handling

Master Rust's robust error handling system with Result, Option, and the ? operator for reliable code

File and I/O Operations

Master Rust's file system operations and I/O handling for robust data persistence and streaming

Smart Pointers

Master Rust's smart pointer types for automatic memory management and safe heap allocation

Concurrency

Master Rust's concurrency model with threads, channels, and synchronization primitives for safe parallel programming

Async Programming

Master asynchronous programming in Rust with futures, async/await, and concurrent execution patterns

Memory Management

Deep dive into Rust's ownership system, borrowing rules, and advanced memory management patterns for safe and efficient code

Macros

Master Rust's metaprogramming system with declarative and procedural macros for code generation and compile-time programming

Attributes

Master Rust's attribute system for conditional compilation, testing, documentation, and code generation

Testing

Master comprehensive testing strategies in Rust including unit tests, integration tests, documentation tests, and testing best practices

Crate Architecture

Master the design and organization of Rust crates including module systems, workspace management, dependency handling, and publishing strategies

Performance and Optimization

Master advanced performance techniques in Rust including profiling, benchmarking, memory optimization, and compiler optimizations

Rust Pattern Matching Quiz

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10

Question 11

Question 12

Question 13

Question 14

Question 15

Question 16

Question 17

Question 18

Question 19

Question 20

Question 21

Question 22

Question 23

Question 24

Question 25

Question 26

Question 27

Question 28

Question 29

Question 30

Question 31

Question 32

Question 33

Question 34

Question 35

Question 36

Question 37

Question 38

Question 39

Question 40

About This Pattern Matching Quiz

What You Will Practise

Other Quiz Categories

QUIZZES IN Rust

Cargo and Project Setup

Variables and Mutability

Data Types

Control Flow

Functions

Ownership

Borrowing

Lifetimes

Strings

Collections

Slices

Pattern Matching

Enums

Struct

Modules

Traits

Generic

Iterators

Closures

Error Handling

File and I/O Operations

Smart Pointers

Concurrency

Async Programming

Memory Management

Macros

Attributes

Testing

Crate Architecture

Performance and Optimization