| 1 | #ifndef INC_TokenStreamSelector_hpp__ | 
| 2 | #define INC_TokenStreamSelector_hpp__ | 
| 3 |  | 
| 4 | /* ANTLR Translator Generator | 
| 5 | * Project led by Terence Parr at http://www.jGuru.com | 
| 6 | * Software rights: http://www.antlr.org/license.html | 
| 7 | * | 
| 8 | * $Id: TokenStreamSelector.hpp,v 1.1 2005-12-02 15:38:02 tim Exp $ | 
| 9 | */ | 
| 10 |  | 
| 11 | #include <antlr/config.hpp> | 
| 12 | #include <antlr/TokenStream.hpp> | 
| 13 | #include <map> | 
| 14 | #include <stack> | 
| 15 |  | 
| 16 | #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE | 
| 17 | namespace antlr { | 
| 18 | #endif | 
| 19 |  | 
| 20 | /** A token stream MUX (multiplexor) knows about n token streams | 
| 21 | *  and can multiplex them onto the same channel for use by token | 
| 22 | *  stream consumer like a parser.  This is a way to have multiple | 
| 23 | *  lexers break up the same input stream for a single parser. | 
| 24 | * Or, you can have multiple instances of the same lexer handle | 
| 25 | *  multiple input streams; this works great for includes. | 
| 26 | */ | 
| 27 | class ANTLR_API TokenStreamSelector : public TokenStream { | 
| 28 | protected: | 
| 29 | /** The set of inputs to the MUX */ | 
| 30 | #ifdef OS_NO_ALLOCATOR | 
| 31 | typedef ANTLR_USE_NAMESPACE(std)less<ANTLR_USE_NAMESPACE(std)string> lessp; | 
| 32 | typedef ANTLR_USE_NAMESPACE(std)map<ANTLR_USE_NAMESPACE(std)string,TokenStream*,lessp> inputStreamNames_coll; | 
| 33 | #else | 
| 34 | typedef ANTLR_USE_NAMESPACE(std)map<ANTLR_USE_NAMESPACE(std)string,TokenStream*> inputStreamNames_coll; | 
| 35 | #endif | 
| 36 | inputStreamNames_coll inputStreamNames; | 
| 37 |  | 
| 38 | /** The currently-selected token stream input */ | 
| 39 | TokenStream* input; | 
| 40 |  | 
| 41 | /** Used to track stack of input streams */ | 
| 42 | #ifdef OS_NO_ALLOCATOR | 
| 43 | typedef ANTLR_USE_NAMESPACE(std)stack<TokenStream*, ANTLR_USE_NAMESPACE(std)deque<TokenStream*> > streamStack_coll; | 
| 44 | #else | 
| 45 | typedef ANTLR_USE_NAMESPACE(std)stack<TokenStream*> streamStack_coll; | 
| 46 | #endif | 
| 47 | streamStack_coll streamStack; | 
| 48 |  | 
| 49 | public: | 
| 50 | TokenStreamSelector(); | 
| 51 | ~TokenStreamSelector(); | 
| 52 |  | 
| 53 | void addInputStream(TokenStream* stream, const ANTLR_USE_NAMESPACE(std)string& key); | 
| 54 |  | 
| 55 | /// Return the stream from which tokens are being pulled at the moment. | 
| 56 | TokenStream* getCurrentStream() const; | 
| 57 |  | 
| 58 | TokenStream* getStream(const ANTLR_USE_NAMESPACE(std)string& sname) const; | 
| 59 |  | 
| 60 | RefToken nextToken(); | 
| 61 |  | 
| 62 | TokenStream* pop(); | 
| 63 |  | 
| 64 | void push(TokenStream* stream); | 
| 65 |  | 
| 66 | void push(const ANTLR_USE_NAMESPACE(std)string& sname); | 
| 67 |  | 
| 68 | /** Abort recognition of current Token and try again. | 
| 69 | *  A stream can push a new stream (for include files | 
| 70 | *  for example, and then retry(), which will cause | 
| 71 | *  the current stream to abort back to this.nextToken(). | 
| 72 | *  this.nextToken() then asks for a token from the | 
| 73 | *  current stream, which is the new "substream." | 
| 74 | */ | 
| 75 | void retry(); | 
| 76 |  | 
| 77 | /** Set the stream without pushing old stream */ | 
| 78 | void select(TokenStream* stream); | 
| 79 |  | 
| 80 | void select(const ANTLR_USE_NAMESPACE(std)string& sname); | 
| 81 | }; | 
| 82 |  | 
| 83 | #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE | 
| 84 | } | 
| 85 | #endif | 
| 86 |  | 
| 87 | #endif //INC_TokenStreamSelector_hpp__ |