Erlang (programming language)/Tutorials/Hello

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Hello World (serial)

Code Example

-module(hello).
-export([start/0]).

start() ->
   io:format("Hello, world!\n").

Analysis of the example

The Hello World program (see above) appears in many programming languages books and articles as a cursory introduction into a language's syntax. The first hello world program was introduced in the book The C Programming Language.

-module(hello) tells the compiler to create a new module(library) called hello. The code tells us the file name for this code: hello.erl.

-export([start/0]). exports a function named start with 0 arguments to the world outside of this module called hello.

start() -> tells the compiler that there is a function named start() with no arguments.

io:format("Hello, world!\n"). will make the program output Hello, world! and a new line (\n) on the screen.