Differences between modules and library modules.

Ulf Wiger <>
Tue Feb 11 15:49:39 CET 2003

On Tue, 11 Feb 2003, Enrique Marcote Peña wrote:

>What are the differences between a module and a "library

I would guess that a library module is one that does not
describe the control a process. lists.erl would be a typical
library module. I don't know that there is a formal division
between library and non-library module (what would you call

>And what about internal exports and external
>exports, are they different for the compiler indeed?

This is mainly a documentation convention. The compiler
doesn't care, but as we have to export functions like
handle_call/3, handle_cast/2, etc, we use a convention to
indicate that these functions are not part of the API, and
should not be called directly. They are exported for
internal use, if you will.

Ulf Wiger, Senior Specialist,
   / / /   Architecture & Design of Carrier-Class Software
  / / /    Strategic Product & System Management
 / / /     Ericsson AB, Connectivity and Control Nodes

More information about the erlang-questions mailing list