Erlang logo
User's Guide

Erlang Reference Manual
User's Guide
Version 6.0

Expand All
Contract All


1 Introduction

1.1  Purpose

This reference manual describes the Erlang programming language. The focus is on the language itself, not the implementation. The language constructs are described in text and with examples rather than formally specified, with the intention to make the manual more readable. The manual is not intended as a tutorial.

Information about this implementation of Erlang can be found, for example, in System Principles (starting and stopping, boot scripts, code loading, error logging, creating target systems), Efficiency Guide (memory consumption, system limits) and ERTS User's Guide (crash dumps, drivers).

1.2  Prerequisites

It is assumed that the reader has done some programming and is familiar with concepts such as data types and programming language syntax.

1.3  Document Conventions

In the document, the following terminology is used:

  • A sequence is one or more items. For example, a clause body consists of a sequence of expressions. This means that there must be at least one expression.
  • A list is any number of items. For example, an argument list can consist of zero, one or more arguments.

If a feature has been added recently, in Erlang 5.0/OTP R7 or later, this is mentioned in the text.

1.4  Complete List of BIFs

For a complete list of BIFs, their arguments and return values, refer to erlang(3).

1.5  Reserved Words

The following are reserved words in Erlang:

after and andalso band begin bnot bor bsl bsr bxor case catch cond div end fun if let not of or orelse receive rem try when xor