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+Doxygen Internals {#mainpage}
+=================
+
+Introduction
+------------
+
+This page provides a high-level overview of the internals of doxygen, with
+links to the relevant parts of the code.
+
+The generic starting point of the application is ofcource the main() function.
+
+Configuration options
+---------------------
+
+Configuration file data is stored in singleton class Config and can be
+accessed using wrapper macros 
+Config_getString(), Config_getInt(), Config_getList(),
+Config_getEnum(), and Config_getBool() depending on the type of the
+option. 
+
+The format of the configuration file (options and types) is defined
+by the file `config.xml`. As part of the build process, 
+the python script `configgen.py` will create a file configoptions.cpp 
+from this, which serves as the input for the configuration file parser
+that is invoked using Config::parse()
+
+Gathering Input files
+---------------------
+
+After the configuration is known, the input files are searched using
+searchInputFiles() and any tag files are read using readTagFile()
+
+Parsing Input files
+-------------------
+
+The function parseFiles() takes care of parsing all files.
+It uses the ParserManager singleton factory to create a suitable parser object
+for each file. Each parser implements the abstract interface ParserInterface.
+
+If the parser indicates it needs preprocessing
+via ParserInterface::needsPreprocessing(), doxygen will call preprocessFile()
+on the file before calling ParserInterface::parseInput().
+
+The result of parsing is a tree of Entry objects 
+These Entry objects are wrapped in a EntryNav object and stored on disk using
+Entry::createNavigationIndex() on the root node of the tree.
+
+Each Entry object roughly contains the raw data for a symbol and is later
+converted into a Definition object.
+
+When a parser finds a special comment block in the input, it will do a first
+pass parsing via parseCommentBlock(). During this pass the comment block
+is split into multiple parts if needed. Some data that is later needed is
+extracted like section labels, xref items, and formulas. 
+Also Markdown markup is processed using processMarkdown() during this pass.
+
+
+
+