MCQs on Introduction to Elixir | Elixir

Elixir is a functional, concurrent, and general-purpose programming language that runs on the BEAM virtual machine, offering impressive scalability and reliability. It is used for building distributed and fault-tolerant applications. This set of 30 multiple-choice questions (MCQs) will cover an overview of Elixir, its installation process, usage of IEx (Interactive Elixir), and the basics of running your first Elixir program.

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30 Multiple-Choice Questions on Elixir Programming

1. What is Elixir primarily designed for?

• A) Object-oriented programming
• B) Building scalable and reliable applications
• C) Data analysis and processing
• D) Web development

2. Which virtual machine does Elixir run on?

• A) JVM
• B) .NET
• C) BEAM
• D) V8

3. Which of the following is NOT a feature of Elixir?

• A) Functional programming
• B) Concurrency
• C) Imperative programming
• D) Fault tolerance

4. What type of language is Elixir?

• A) Object-oriented
• B) Imperative
• C) Functional
• D) Logic-based

5. What does BEAM stand for in the context of Elixir?

• A) Binary Execution and Application Manager
• B) Basic Erlang Architecture Module
• C) Bogus Execution and Application Manager
• D) Erlang’s virtual machine

6. Which programming paradigm is central to Elixir?

• A) Object-oriented
• B) Procedural
• C) Functional
• D) Declarative

7. What is one of Elixir’s strengths in terms of concurrency?

• A) Single-threaded execution
• B) Multiple processes without shared memory
• C) Synchronous execution only
• D) Limited concurrency

8. How do Elixir processes communicate with each other?

• A) Through shared memory
• B) By passing messages
• C) By direct function calls
• D) Through signals

9. Which of the following is a feature of the BEAM virtual machine?

• A) Memory management
• B) Concurrency support
• C) Fault tolerance
• D) All of the above

10. What is the role of the Elixir interactive shell (IEx)?

• A) To compile Elixir programs
• B) To execute Elixir code interactively
• C) To create new projects
• D) To manage the Elixir installation

11. What command starts the Elixir interactive shell (IEx)?

• A) iex
• B) elixir
• C) elixir start
• D) start iex

12. What file extension do Elixir source files use?

• A) .elx
• B) .ex
• C) .erl
• D) .exs

13. How can you evaluate an expression in the Elixir interactive shell (IEx)?

• A) Using the eval command
• B) By typing the expression directly into the shell
• C) By running the run command
• D) By using run_expression

14. What is the basic structure of an Elixir program?

• A) Functions and variables
• B) Classes and objects
• C) Modules and functions
• D) Blocks and statements

15. How do you define a function in Elixir?

• A) Using function keyword
• B) Using def keyword
• C) Using fn keyword
• D) Using func keyword

16. How do you declare a module in Elixir?

• A) module MyModule
• B) module :my_module
• C) defmodule MyModule
• D) module MyModule

17. How do you execute an Elixir program from a file?

• A) By using the elixir command followed by the file name
• B) By using the iex command
• C) By compiling the file with compile
• D) By running the elixir_run command

18. Which command can you use to compile an Elixir file?

• A) elixir compile
• B) elixirc
• C) compile_elixir
• D) compile.exs

19. What is an Elixir “process”?

• A) A type of thread in the operating system
• B) An isolated unit of computation with its own state
• C) A function in Elixir code
• D) A single program running in a shell

20. Which command prints the current version of Elixir?

• A) elixir –version
• B) iex –version
• C) elixir version
• D) elixir -v

21. What command is used to install Elixir on a system?

• A) apt-get install elixir
• B) elixir install
• C) brew install elixir
• D) elixir setup

22. How can you start a new Elixir project?

• A) elixir new project
• B) mix new project
• C) elixir create project
• D) elixir init project

23. Which command is used to run a project in Elixir?

• A) mix run
• B) elixir run
• C) run mix
• D) mix execute

24. How can Elixir handle errors?

• A) By raising exceptions and stopping the process
• B) By ignoring errors
• C) By using the try and catch keywords
• D) By using its built-in error handling mechanisms like try/catch and error

25. Which is the best way to ensure fault tolerance in an Elixir application?

• A) Use of processes and supervision trees
• B) Adding try-catch blocks
• C) Use of threads
• D) None of the above

26. How does Elixir implement concurrency?

• A) Through threads
• B) Using actors and message-passing
• C) By multi-threading
• D) Through multi-process management

27. Which of the following is true about Elixir’s data types?

• A) It has mutable data structures
• B) It supports both mutable and immutable data
• C) All data structures are immutable
• D) It only supports mutable data

28. What is the mix tool used for in Elixir?

• A) Managing dependencies and compiling code
• B) Running shell commands
• C) Managing user interfaces
• D) Managing databases

29. What type of system is Elixir best suited for?

• A) Small, single-threaded applications
• B) Distributed, fault-tolerant, and concurrent systems
• C) Desktop applications
• D) Web scraping scripts

30. What is the first step to writing your first Elixir program?

• A) Write the main() function
• B) Install Elixir and open IEx
• C) Write a class
• D) Use an IDE to create a project

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Answer Key

Qno	Answer (Option with the text)
1	B) Building scalable and reliable applications
2	C) BEAM
3	C) Imperative programming
4	C) Functional
5	D) Erlang’s virtual machine
6	C) Functional
7	B) Multiple processes without shared memory
8	B) By passing messages
9	D) All of the above
10	B) To execute Elixir code interactively
11	A) iex
12	B) .ex
13	B) By typing the expression directly into the shell
14	C) Modules and functions
15	B) Using def keyword
16	C) defmodule MyModule
17	A) By using the elixir command followed by the file name
18	B) elixirc
19	B) An isolated unit of computation with its own state
20	D) elixir -v
21	A) apt-get install elixir
22	B) mix new project
23	A) mix run
24	D) By using its built-in error handling mechanisms like try/catch and error
25	A) Use of processes and supervision trees
26	B) Using actors and message-passing
27	C) All data structures are immutable
28	A) Managing dependencies and compiling code
29	B) Distributed, fault-tolerant, and concurrent systems
30	B) Install Elixir and open IEx