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1/// \page using Using the ANTLR3 C Target
2///
3/// \section intro Introduction
4///
5/// Using the ANTLR target involves gaining knowledge of a number of elements:
6///
7/// -# Writing ANTLR grammars (not covered in this manual);
8/// -# How ANTLR works (not covered in this manual);
9/// -# How to use the \@sections with the C target
10/// -# Interoperation with the runtime within rule actions;
11/// -# Implementing custom versions of the standard library methods;
12///
13/// If you are as yet unfamiliar with how ANTLR works in general, then
14/// it is suggested that you read the various <a href="http://www.antlr.org/wiki">wiki pages</a> concerned with
15/// getting started. However there are a few things that you should note:
16///
17/// - The lexer is independent of the parser. You \b cannot control the lexer from within the parser;
18/// - The tree parser is independent of the parser. You \b cannot control the parser from within the tree parser(s);
19/// - Each tree parser is independent of other tree parsers.
20///
21/// This means that your lexer runs first and consumes all the input stream until
22/// you stop it programmatically, or it reaches the end of the input stream. It produces
23/// a complete stream of tokens, which the parser then consumes.
24///
25/// \section Using \@sections in a C Targeted Grammar
26///
27/// Within a grammar file there are a number of special sections you can add that cause the
28/// code within them to be placed at strategic points in the generated code such as
29/// before or after the #include statements in the .c file, within the generated header file
30/// or within the constructor for the recognizer.
31///
32/// Many of the \@sections used within a Java targeted grammar have some equivalent function within a
33/// C targeted grammar, but their use may well be subtly different. There are also additional sections
34/// that have meaning only within a grammar targeted for the C runtime.
35///
36/// Detailed documentation of these sections is given here: \subpage atsections
37///
38/// \section interop Interoperation Within Rule Actions
39///
40/// Rule actions have a limited number of elements they can access by name, independently of the
41/// target language generated. These are elements such as $line, $pos, $text and so on. Where the
42/// $xxx returns a basic type such as \c int, then you can use these in C as you would in the Java
43/// target, but where a reference returns a string, you will get a pointer to the C runtime
44/// string implementation #pANTLR3_STRING. This will give you access to things like token text
45/// but also provides some convenience methods such as #pANTLR3_STRING->substring() and #pANTLR3_STRING->toUTF8().
46///
47/// The generated code provides a number of C MACROs, which make it easier to access runtime
48/// components. Always use these macros when available, to protect your action code from changes
49/// to the underlying implementation.
50///
51/// Detailed documentation of macros and rule action interoperation is given here: \subpage interop
52///
53/// \section Custom Implementing Customized Methods
54///
55/// Unless you wish to create your own tree structures using the built in ANTLR AST rewriting
56/// notation, you will rarely need to override the default implementation of runtime methods. The
57/// exception to this will be the syntax err reporting method, which is essentially a stub function
58/// that you will usually want to provide your own implementation for. You should consider the built in function
59/// displayRecognitionError() as an example of where to start as there can be no really useful
60/// generic error message display.
61///
62///