Systemmodell-basierte Definition objektbasierter ...

C.1 Gemeinsam genutzte Sprachteile 281
216 (
217 // HEX
218 ((’x’|’X’) ((HEX_DIGIT)+ | (’.’ (HEX_DIGIT)+) | HEX_EXPONENT)) =>
219 (
220 (’x’|’X’)
221 // The decimal exponent and the float suffix look like
222 // hex digits, hence the (...)* doesn’t know when to stop
223 // (-> ambig). ANTLR resolves it correctly by matching
224 // immediately. It is therefore ok to hush warning.
225 (options {warnWhenFollowAmbig=false;}: HEX_DIGIT)*
226 {isHex = true;}
227 )
228 |
229 // FLOAT or DOUBLE with leading zero
230 ((’0’..’9’)+ (’.’|DECIMAL_EXPONENT|FLOAT_SUFFIX)) => (’0’..’9’)+
231 |
232 // OCTAL
233 (’0’..’7’)+
234 )?
235 )
236 |
237 // NON-ZERO DECIMAL
238 ((’1’..’9’) (’0’..’9’)* {isDecimal=true; _ttype = NUM_INT;})
239 )
240 {
241 if (LA(1)==’.’ && LA(2)==’.’)
242 isDoubleDot = true;
243 else
244 isDoubleDot = false;
245 }
246 (
247 (’l’|’L’) {_ttype = NUM_LONG;}
248
249 // only check to see if it’s a float if looks like decimal so far
250 |
251 {isDecimal && !isDoubleDot}?
252 (
253 {isHex}?
254 ( // exponent is mandatory for floating point hex digits
255 ’.’ (HEX_DIGIT)* HEX_EXPONENT (t=FLOAT_SUFFIX)?
256 |
257 HEX_EXPONENT (t=FLOAT_SUFFIX)?
258 |
259 t=FLOAT_SUFFIX
260 )
261 |
262 (
263 ’.’ (’0’..’9’)* (DECIMAL_EXPONENT)? (t=FLOAT_SUFFIX)?
264 |
265 DECIMAL_EXPONENT (t=FLOAT_SUFFIX)?
266 |
267 t=FLOAT_SUFFIX
268 )
269 )
270 {
271 if (t != null && t.getText().toUpperCase().indexOf(’F’) >= 0) {
272 _ttype = NUM_FLOAT;
273 }
274 else {
275 _ttype = NUM_DOUBLE; // assume double
276 }
277 }