# Erlang Cheatsheet
## Overview of unique features
- Functional programming language
- Designed for building concurrent and distributed systems
- Uses lightweight processes instead of threads
- Supports hot-swapping of code
- Can be used for building telecom and messaging systems
## Variables
```erlang
% Declare a variable
X = 42.
% Declare a constant
- define(Y, 10).
% Declare a tuple
MyTuple = {apple, 3}.
% Declare a list
MyList = [1, 2, 3].
```
## Functions
```erlang
% Define a function
add(X, Y) ->
X + Y.
% Call a function
Result = add(3, 4).
```
## Loops
```erlang
% Define a loop
my_loop(I) ->
case I > 10 of
true -> done;
false -> my_loop(I + 1)
end.
```
## Conditionals
```erlang
% Define an if-else statement
max(X, Y) ->
if X > Y ->
X;
true ->
Y
end.
```
## Processes
```erlang
% Define a process
my_process() ->
receive
{From, Message} ->
From ! {ok, Message},
my_process()
end.
% Start a process
Pid = spawn(my_module, my_process, []).
% Send a message to a process
Pid ! {self(), "hello"}.
% Receive a message from a process
receive
{ok, Message} -> io:format("Received ~p", [Message])
end.
```
## Resources
- [Erlang documentation](
https://www.erlang.org/docs)
- [Erlang tutorial](
https://learnyousomeerlang.com/content)
- [Erlang forum](
https://stackoverflow.com/questions/tagged/erlang) for community support and troubleshooting.
