ELIXIR

Question 1

Who is the Brazilian software engineer and co-founder of Plataformatec that created Elixir?

Answer 1

José Valim

Question 2

In what year did José Valim publish version 0.5 of Elixir?

Answer 2

2012

Question 3

Elixir was built on top of which virtual machine originally created to power telecom systems?

Answer 3

Erlang virtual machine (BEAM)

Question 4

What is the name of the high-performance web framework built on Elixir for scalable, real-time web applications?

Answer 4

Phoenix Framework

Question 5

Elixir follows the “let it crash” philosophy to recover gracefully from failures.
True or False

Answer 5

True

Question 6

The latest version of Elixir, version 1.19, was released in what month and year?

Answer 6

October 2025

Question 7

What is the name of the build tool in Elixir that provides tasks for creating, compiling, and testing projects?

Answer 7

Mix

Question 8

Elixir uses an interpreter as its translator program rather than a compiler.
True or False

Answer 8

False

Question 9

Elixir emphasizes mutable data, meaning data can be changed once created.
True or False

Answer 9

False

Question 10

Elixir source code written in .ex files is compiled into what type of bytecode?

Answer 10

BEAM bytecode

Question 11

Create a statement in Elixir that explicitly binds the integer value 10 to the variable x.

Answer 11

x = 10

Question 12

Elixir natively supports user-defined subrange or enumerated types.
True or False

Answer 12

False

Question 13

What built-in data structure in Elixir uses square brackets and is optimized for sequential traversal?

Answer 13

Lists

Question 14

What built-in data structure in Elixir uses curly brackets and stores elements contiguously in memory for fast indexed access?

Answer 14

Tuples

Question 15

Create a statement in Elixir that defines a tuple containing the atom :ok and the string “hello”.

Answer 15

{ :ok, “hello” }

Question 16

What is the built-in data structure module in Elixir used for handling collections where uniqueness matters?

Answer 16

MapSet

Question 17

What operator is used to concatenate strings in Elixir?

Answer 17

<>

Question 18

In Elixir, abstract data types are implemented using built-in language constructs rather than modules and structs.
True or False

Answer 18

False

Question 19

What keyword is used in Elixir to define fixed data shapes within a module?

Answer 19

defstruct

Question 20

Elixir uses the ASCII character set by default, preventing the use of international characters in strings.
True or False

Answer 20

False

Question 21

In Elixir, what operator is used for pattern matching and variable binding?

Answer 21

= (Match operator)

Question 22

What is the name of the ^ operator used to prevent rebinding a variable in Elixir?

Answer 22

Pin operator

Question 23

The |> symbol is known as the pipeline operator in Elixir.
True or False

Answer 23

True

Question 24

What delimiter separates patterns and expressions in anonymous functions and control structures like case and cond?

Answer 24

-> (Arrow operator)

Question 25

Elixir code blocks are enclosed using curly braces. True or False

Answer 25

False

Question 26

What symbol is used to introduce comments in Elixir?

Answer 26

(Hash symbol)

Question 27

What punctuation mark is used to prefix atoms in Elixir?

Answer 27

: (Colon)

Question 28

Identifiers for variables and functions in Elixir must be written in CamelCase. True or False

Answer 28

False

Question 29

What macro is used to define a public function that forms a module's public API?

Answer 29

def

Question 30

What macro is used to define a private, internal function accessible only within the defining module?

Answer 30

defp

Question 31

Create a statement in Elixir that declares a namespace or module named Calculator.

Answer 31

defmodule Calculator do

Question 32

Create a statement in Elixir that defines a public function named add that takes two parameters, a and b.

Answer 32

def add(a, b) do

Question 33

Elixir enforces strict lexical scoping and immutable data, meaning there are no shared global variables. True or False

Answer 33

True

Question 34

What module attribute is used in Elixir to attach documentation metadata immediately preceding a function definition?

Answer 34

@doc

Question 35

In Elixir, the division operator always yields a floating-point result. True or False

Answer 35

True

Question 36

What strict boolean operator in Elixir returns true only if both boolean operands are true?

Answer 36

and

Question 37

What macro evaluates a boolean condition to implement two-way selection in Elixir?

Answer 37

if (or unless)

Question 38

Elixir relies heavily on traditional pre-test (while) and post-test (do-while) loops for iteration. True or False

Answer 38

False

Question 39

Iteration in Elixir is implemented primarily through what mechanism?

Answer 39

Recursion

Question 40

What primitive function allows a developer to detach a subprogram to run in a separate, isolated process concurrently?

Answer 40

spawn

Question 41

Elixir implements traditional symmetric coroutines with explicit yield and resume operators. True or False

Answer 41

False

Question 42

What module facilitates lazy evaluation in Elixir, allowing a subprogram to generate a sequence of values one at a time?

Answer 42

Stream module

Question 43

Create a statement in Elixir that explicitly halts or immediately terminates the runtime system.

Answer 43

System.halt

Question 44

What function is explicitly used to perform integer division in Elixir?

Answer 44

div

Question 45

In Elixir, an explicit return statement is required to exit a subroutine with a value. True or False

Answer 45

False

Question 46

What compiler feature ensures that recursive self-reference does not consume additional stack frames in Elixir?

Answer 46

Tail-call optimization

Question 47

What is the output of the following program snippet in Elixir? result = 5 * 2 IO.puts("Result is #{result}")

Answer 47

Result is 10

Question 48

What is the output of the following program snippet in Elixir? Elixir [1, true, 2, false, 3, true] -- [true, false]

Answer 48

[1, 2, 3, true]

Question 49

What is the output of the following program snippet in Elixir? "elixir" |> String.upcase() |> String.reverse()

Answer 49

"RIXILE"

Question 50

What is the output of the following program snippet in Elixir? Stream.cycle([1, 2, 3]) |> Stream.take(5) |> Enum.to_list()

Answer 50

[1, 2, 3, 1, 2]

Question 51

- What is the file extension for Elixir source files that are compiled?

Answer 51

.ex

Question 52

- Which Elixir primitive enables a subprogram to run concurrently in a separate process?

Answer 52

spawn/1

Question 53

- What operator prevents variable rebinding during pattern matching?

Answer 53

^ (pin operator)

Question 54

- What Elixir construct allows multi-way selection and uses pattern matching to determine which branch to execute?

Answer 54

case

Question 55

- Name the virtual machine that runs Elixir programs.

Answer 55

BEAM (Erlang Virtual Machine)

Question 56

- In Elixir, variables are mutable by default, allowing values to be directly changed in memory. True or False

Answer 56

False

Question 57

- The MapSet module in Elixir is used to manage collections of unique values and supports operations like union, intersection, and difference. True or False

Answer 57

True

Question 58

- The ++ and -- operators modify the original list in-place when concatenating or subtracting elements. True or False

Answer 58

False

Question 59

- Elixir source files with the .exs extension are compiled before execution, similar to .ex files. True or False

Answer 59

False

Question 60

- In Elixir, the do … end keywords are used to delimit code blocks instead of curly braces {}. True or False

Answer 60

True

Question 61

- What is the output of the program? a = 3 b = 7 c = 10 {[x, y], z} = {[b, a], c} x = x * 2 y = y + z z = z + y IO.inspect({x, y, z})

Answer 61

{14, 13, 23}

Question 62

- Fill in the missing code so that the variable result is bound to "even" when n is even and "odd" otherwise. n = 7 result = case __________ do __________ -> "even" __________ -> "odd" end IO.puts(result)

Answer 62

(1) rem(n, 2) (2) 0 (3) _

Question 63

- Analyze the following recursive function. What value is printed to the console? defmodule MathOps do def sum([], acc), do: acc def sum([h | t], acc), do: sum(t, acc + h) end IO.inspect(MathOps.sum([2, 4, 6], 0))

Answer 63

12

Question 64

- Based on thIs expression, what list is produced? result = Stream.cycle([:a, :b]) |> Stream.take(4) |> Enum.to_list() IO.inspect(result)

Answer 64

[:a, :b, :a, :b]

Question 65

- Fill in the blank to complete the output string. parent = self() spawn(fn -> send(parent, {:msg, 42}) end) receive do {:msg, value} -> IO.puts("Received: #{________}") end

Answer 65

value