Grammar for Compilation Descriptions 

Compilation descriptions are based on the general grammar for description files and the naming conventions for module files.

<compile_description> = {<block>} | EMPTY

<line> = <comp_desc_line>

<comp_desc_line> = <comment_line> | <comp_line> | <def_line> | <option_line> | EMPTY

<comp_line> = (<source_spec> | <reg_source>)<token_sep>{<option>}<new_line>

<reg_source> = regex(<regex>) | ([<source_id>]*[<lang_id>][<variant>])

<source_id> = g | h | i | v

<regex> =Regular expression (according to GNU standard)