1changes31(3)                        ANTLR3C                       changes31(3)
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NAME

6       changes31 - Changes in 3.1 from 3.0 The following changes have taken
7       place from 3.0 to 3.1. Some of them may require minor changes to your
8       grammar files or the programs that invoke your grammar. Please take the
9       time to read through this list as it may save you time later.
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Constructor Return Values

12       In previous releases the return value from both the generated
13       constructors and built in constructor functions would return a value of
14       -1 or -2 if a problem occurred. However, the only problem that can
15       really occur is lack of memory, hence to avoid the remote change that
16       some memory allocation scheme would return an address of -1 for a
17       pointer, the return address is now NULL if there was no memory
18       available. The old macros for this mechanism have been removed which
19       will force you to read this information. You now need only check the
20       return address for NULL, or you could not bother doing that and join
21       with 95% of the world's C code.
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Tree Parser Rewrites

24       The 3.1 runtime now supports tree rewrites from tree parsers. See the
25       main ANTLR documentation for more details. This beta version contains
26       knownissues regarding the release of mmeory allocated to tree nodes
27       when they are rewritten in some combinations of re-writing tree
28       parsers. These issues will be corrected before release.
29

ANTLRWorks Debugger

31       The ANTLRWorks debugger is now fully supported by this version of the
32       runtime. It supports remote debugging only (you cannot generate C,
33       compile and debug it from the ANTLRWorks IDE.) However both parser and
34       tree parser debugging is supported providing you are using a version of
35       ANTLRWorks that supports tree parser debugging. Generate the C code
36       with the -debug option of the ANTLR tool, as per any other target.
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38       Note that when you invoke your debugging version of the parser, it will
39       appear to hang but is in fact waiting on a local TCP socket connection
40       from the ANTLRWorks debugger. As the target environment is unknown, it
41       is not prudent to generate notification status messages using something
42       like printf, as the target environment may not have a console or
43       implement printf.
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Macro Changes

46       Prior to the 3.1 release, accessing the token source of a lexer
47       required knowledge of where the token source pointer was located wihtin
48       the lexer. In 3.1, the token source was burried further in the innards
49       of the C runtime and such knowledge is considerd irreleavant and
50       confusing. Hence, when creating a token stream from a token source, it
51       is now mandatory to use the new C macro TOKENSOURCE(lxr), which will
52       expand to point at the token source interface. This MACRO will be
53       maintained across future versions. You can see how to use it in the
54       downloadable examples, avaiable from the downloads page of the ANTLR
55       web site. Here is the relevant code for creating a token stream,
56       extracted from those examples:
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58       tstream = antlr3CommonTokenStreamSourceNew(ANTLR3_SIZE_HINT, TOKENSOURCE(lxr));
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60Version 3.3.1                   Tue Jan 28 2020                   changes31(3)
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