How to Use the Erlang Compiler

To use the Erlang Compiler, follow these steps:

  1. In the code editor, write your Erlang code.
  2. Click the "RUN" button to compile and run your code.
  3. The output will be displayed in the console below the code editor.

Taking Inputs

In Erlang, you can take inputs from the user in various ways. Here are some examples:

String Input

io:format("Enter a string: "),
Input = io:get_line(''),
io:format("You entered: ~s", [Input]).

Number Input

io:format("Enter a number: "),
{ok, [Num]} = io:fread("", "~d"),
io:format("You entered: ~p", [Num]).

Importing Libraries

Erlang has a rich set of built-in libraries that can be used in your programs. Here are some examples:

Using the Math Library

Result = math:sqrt(25),
io:format("Square root of 25 is ~p", [Result]).

Using the Lists Library

List = lists:seq(1, 5),
io:format("List of numbers: ~p", [List]).

Syntax 101

Erlang is a functional, concurrent, general-purpose programming language and runtime system. Here's a primer on the major syntax basics of Erlang:


Variables in Erlang must start with a capital letter or an underscore.

Name = "John Doe".
Age = 25.

Control Structures

Erlang includes control structures such as if, case, and receive.

% If
    Age > 18 ->
    true ->

% Case
case Day of
    "Monday" ->
        io:format("Start of the work week");
    "Friday" ->
        io:format("End of the work week");
    _ ->


Functions in Erlang are grouped in modules.


greet(Name) ->
    io:format("Hello, ~s", [Name]).


Lists in Erlang can hold elements of any type.

List = [1, 2, 3, 4, 5].

Erlang Online Test

An Erlang online test is an effective way to assess an individual's Erlang programming skills. These tests typically include a mix of theoretical questions and practical coding challenges. By attempting these tests, candidates can demonstrate their understanding of Erlang concepts, their problem-solving abilities, and their proficiency in writing efficient code. Erlang online tests are commonly used in technical interviews, coding bootcamps, and online learning platforms to gauge a learner's understanding and proficiency in Erlang.