JSDOC/TokenStream.vala
[gnome.introspection-doc-generator] / JSDOC / TokenStream.vala
1
2 /**
3  * @class TokenStream
4  * 
5  * BC notes:
6  * 
7  * nextT => nextTok
8  * lookT => lookTok
9  * 
10  */
11
12
13 namespace JSDOC {
14
15         errordomain TokenStreamError {
16             ArgumentError
17     }
18         public class TokenStream : Object
19         {
20         
21                 Gee.ArrayList<Token> tokens;
22                 int cursor; // where are we in the stream.              
23         
24         
25                 public TokenStream(Gee.ArrayList<Token> tokens) {
26                  
27                         this.tokens = tokens;
28
29                         this.rewind();
30                 }
31         
32
33                 
34                 public void rewind() {
35                     this.cursor = -1;
36                 }
37
38                 /**
39                     @type JSDOC.Token
40                 */
41                 public Token? look (int n, bool considerWhitespace) 
42                 {
43
44
45                     if (considerWhitespace == true) {
46                     
47                         if (this.cursor+n < 0 || this.cursor+n > (this.tokens.size -1)) {
48                             return new Token("", "VOID", "START_OF_STREAM");
49                         }
50                         return this.tokens.get(this.cursor+n);
51                     }
52                     
53
54                 var count = 0;
55                 var i = this.cursor;
56
57                 while (true) {
58                     if (i < 0) {
59                                 return new Token("", "VOID", "START_OF_STREAM");
60                         }
61                     if (i > this.tokens.size) {
62                                 return new Token("", "VOID", "END_OF_STREAM");
63                         }
64
65                     if (i != this.cursor && this.tokens.get(i).is("WHIT")) {
66                                 i += (n < 0) ? -1 : 1;
67                         continue;
68                     }
69                     
70                     if (count == n) {
71                         return this.tokens.get(i);
72                     }
73                     count++;
74                     i += (n < 0) ? -1 : 1;
75                 }
76
77                 return new Token("", "VOID", "STREAM_ERROR"); // because null isn't an object and caller always expects an object
78                     
79                 }
80
81                 public int lookFor  (string data)
82                 {
83                     // non tree version..
84                     var i = this.cursor < 0 ? 0 : this.cursor ;
85                     
86                     while (true) {
87                         if (i >= this.tokens.size) {
88                                 return -1;
89                         }
90                         if (this.tokens.get(i).data == data) {
91                             return i;
92                         }
93                         i++;
94                         
95                     }
96                     // should not get here!
97                     return -1;
98
99                 }
100
101
102                 /**
103                  * look ahead (or back) x number of tokens (which are not comment or whitespace)
104                  * ?? used any more?
105                  */
106                 public Token lookTok (int n) {
107
108
109                     
110                     var count = 0;
111                     var i = this.cursor;
112
113                     while (true) {
114                        // print(i);
115                         if (i < 0) {
116                             if (n > -1) {
117                                 i = 0; 
118                                 count++;
119                                 continue;
120                                 
121                             }
122                             return  new Token("", "VOID", "END_OF_STREAM");
123                         }
124                         if (i > this.tokens.size) {
125                                 return  new Token("", "VOID", "END_OF_STREAM");
126                         }
127
128                         if (i != this.cursor && ( this.tokens.get(i).is("WHIT") || this.tokens.get(i).is("COMM"))) {
129                             i += (n < 0) ? -1 : 1;
130                             continue;
131                         }
132                         
133                         if (count == n) {
134                             return this.tokens.get(i);
135                         }
136                         count++;
137                         i += (n < 0) ? -1 : 1;
138                     }
139                 // should never get here..
140                     return  new Token("", "VOID", "END_OF_STREAM");; // because null isn't an object and caller always expects an object;
141                     
142                 }
143
144                 /**
145                  *  @return {Token|null}
146                  * next token (with white space)
147                  */
148                     
149                    
150                 public Token? next() {
151                 
152                 
153                     //if (typeof howMany == "undefined") howMany = 1;
154                     // if (howMany < 1) { return  null;                 }
155                     
156                     if (this.cursor+1 >= this.tokens.size) {
157                         return null;
158                 }
159                     this.cursor++;
160                     return this.tokens.get(this.cursor);
161
162                 }
163                 
164             public Gee.ArrayList<Token> nextM(uint howMany) {
165                 
166                     //if (typeof howMany == "undefined") howMany = 1;
167                     if (howMany < 2) { 
168                                 throw new  TokenStreamError.ArgumentError("nextM called with wrong number : %d", (int)howMany);
169                     }
170                     var got = new Gee.ArrayList<Token>();
171
172                     for (var i = 1; i <= howMany; i++) {
173                         if (this.cursor+i >= this.tokens.size) {
174                             return null;
175                         }
176                         got.add(this.tokens.get(this.cursor+i));
177                     }
178                     this.cursor += howMany;
179                     
180                         return got;
181                 }
182                 
183                 
184                 
185                 
186                 // what about comments after 'function'...
187                 // is this used ???
188                 public Token? nextTok() {
189                     return this.nextNonSpace();
190                 }
191                 
192                 public Token? nextNonSpace ()
193                 {
194                     
195                     while (true) {
196                         tok = this.next();
197                         if (tok == null) {
198                             return null;
199                         }
200                         if (tok.is("WHIT") ||  tok.is("COMM")) {
201                             continue;
202                         }
203                         return tok;
204                     }
205                 }
206                 
207                 /**
208                  *  balance 
209                  * -- returns all the tokens betweeen and including stop token eg.. from {... to  }
210                  * @param start {String}  token name or data (eg. '{'
211                  * @param stop {String} (Optional) token name or data (eg. '}'
212                  */
213                 public Gee.ArrayList<Token> balance (string start, string stop = "") {
214                     
215                     // accepts names or "{" etc..
216                     
217                     start = Lang.punc(start) == null ? start : Lang.punc(start);
218                     
219                     if (stop=="") {
220                                 stop = Lang.matching(start);
221                         }
222                         if (stop == null) {
223                                 throw new JSDOC.TokenStreamError("balance called with invalid start/stop : %s",start);
224                         }
225                     
226                     var depth = 0;
227                     var got = new Gee.ArrayList<Token>();
228                     var started = false;
229                     //Seed.print("START:" + start);
230                     //Seed.print("STOP:" + stop);
231                     
232                     while ((token = this.look())) {
233                         if (token.is(start)) {
234                       //      Seed.print("balance: START : " + depth + " " + token.data);
235                             depth++;
236                             started = true;
237                         }
238                         
239                         if (started) {
240                             got.push(token);
241                         }
242                         
243                         if (token.is(stop)) {
244                             depth--;
245                         //    Seed.print("balance: STOP: "  + depth + " " + token.data);
246                             if (depth < 1) {
247                                         return got;
248                                 }
249                         }
250                         if (!this.next()) {
251                                 break;
252                         }
253                     }
254                     return new Gee.ArrayList<Token>();
255                 }
256
257                 public Token getMatchingToken(string start, string stop) {
258                     var depth = 0;
259                     var cursor = this.cursor;
260                     
261                     if (!start) {
262                         start = Lang.matching(stop);
263                         depth = 1;
264                     }
265                     if (!stop) stop = Lang.matching(start);
266                     
267                     while ((token = this.tokens[cursor])) {
268                         if (token.is(start)) {
269                             depth++;
270                         }
271                         
272                         if (token.is(stop) && cursor) {
273                             depth--;
274                             if (depth == 0) return this.tokens[cursor];
275                         }
276                         cursor++;
277                     }
278                     return false;
279                 }
280
281                 public Gee.ArrayList<Token> insertAhead(Token token) {
282                     this.tokens.splice(this.cursor+1, 0, token); // fixme...
283                 }
284                  
285                 public Gee.ArrayList<Token> remaining() {
286                     var ret = new Gee.ArrayList<Token>();
287                     while (true) {
288                         var tok = this.look(1,true);
289                         if (tok.is("VOID")) {
290                             return ret;
291                         }
292                         ret.push(this.next(1));
293                     }
294                 }
295                  
296                 /*
297                 arrayToString : function(ar) {
298                     console.log(typeof(ar));
299                     var ret = [];
300                     ar.forEach(function(e) {
301                         ret.push(e.data);
302                     })
303                     return ret.join('');
304                 },
305                 dump: function(start, end)
306                 {
307                     start = Math.max(start || 0, 0);
308                     end = Math.min(end || this.tokens.length, this.tokens.length);
309                     var out='';
310                     for (var i =start;i < end; i++) {
311                         
312                         out += (this.tokens[i].outData == false) ? this.tokens[i].data : this.tokens[i].outData;
313                     };
314                     print(out);
315                 }
316                 */
317         }
318 }
319