Introduction
============

It was explained in [:external:ref:`D1.01.01 <D1.01.01>`] how a developer could "overload" Code_Aster with personal sources. The sources we are talking about here are:


* FORTRAN, or C routines


* Python sources


* catalogs,


* test cases.

A classic development of Aster generally results in:


* the modification of certain sources,


* the writing of new sources.

The modification of sources requires their prior extraction (copying) from the official sources. Paragraph § :ref:`2 <RefHeading__34486704>`
`<.. /wiki/doku.php %3FID=en:P03_Dev:D02:D02:D20101_Regles_Extrac_Restit_Src%23Regles_d_Extraction>`_ is about extraction rules.

Once the development is complete, it can be "restored": the official sources are then updated. Paragraph § :ref:`3 <RefHeading__34493966>`
`<.. /wiki/doku.php %3FID=en:P03_Dev:D02:D02:D20101_Regles_Extrac_Restit_Src%23Regles_de_Restition>`_ concerns the return rules.


.. _RefHeading__34486704: