changes31.dox revision 324c4644fee44b9898524c09511bd33c3f12e2df 
1/// \page changes31 Changes in 3.1 from 3.0
2///
3/// The following changes have taken place from 3.0 to 3.1. Some of
4/// them may require minor changes to your grammar files or the
5/// programs that invoke your grammar. Please take the time to read
6/// through this list as it may save you time later.
7///
8/// \section returns Constructor Return Values
9///
10/// In previous releases the return value from both the generated constructors and
11/// built in constructor functions would return a value of -1 or -2 if a problem
12/// occurred. However, the only problem that can really occur is lack of memory, 
13/// hence to avoid the remote change that some memory allocation scheme would return
14/// an address of -1 for a pointer, the return address is now NULL if there was
15/// no memory available. The old macros for this mechanism have been removed which
16/// will force you to read this information. You now need only check the return
17/// address for NULL, or you could not bother doing that and join with 95% of the world's
18/// C code.
19///
20/// \section trees Tree Parser Rewrites
21///
22/// The 3.1 runtime now supports tree rewrites from tree parsers. See the main ANTLR
23/// documentation for more details. This beta version contains \subpage knownissues regarding
24/// the release of mmeory allocated to tree nodes when they are rewritten in some combinations
25/// of re-writing tree parsers. These issues will be corrected before release.
26///
27/// \section debugger ANTLRWorks Debugger
28///
29/// The ANTLRWorks debugger is now fully supported by this version of the runtime. It
30/// supports remote debugging only (you cannot generate C, compile and debug it from the
31/// ANTLRWorks IDE.) However both parser and tree parser debugging is supported providing 
32/// you are using a version of ANTLRWorks that supports tree parser debugging. Generate
33/// the C code with the -debug option of the ANTLR tool, as per any other target.
34///
35/// Note that when you invoke your debugging version of the parser, it will appear to hang
36/// but is in fact waiting on a local TCP socket connection from the ANTLRWorks debugger. As the
37/// target environment is unknown, it is not prudent to generate notification status messages
38/// using something like printf, as the target environment may not have a console or implement
39/// printf.
40///
41/// \section macros Macro Changes
42///
43/// Prior to the 3.1 release, accessing the token source of a lexer required knowledge of where
44/// the token source pointer was located wihtin the lexer. In 3.1, the token source was burried
45/// further in the innards of the C runtime and such knowledge is considerd irreleavant and confusing.
46/// Hence, when creating a token stream from a token source, it is now mandatory to use the new
47/// C macro TOKENSOURCE(lxr), which will expand to point at the token source interface. This MACRO
48/// will be maintained across future versions. You can see how to use it in the downloadable 
49/// examples, avaiable from the downloads page of the ANTLR web site. Here is the relevant code
50/// for creating a token stream, extracted from those examples:
51///
52/// \code
53/// tstream = antlr3CommonTokenStreamSourceNew(ANTLR3_SIZE_HINT, TOKENSOURCE(lxr));
54/// \endcode
55///
56
57