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 ///
