| 356 | |
| 357 | |
| 358 | static vector<Item> CreateOperatorGroups(const vector<Item>& items) |
| 359 | { |
| 360 | vector<Item> result, pending; |
| 361 | bool hasOperators = false; |
| 362 | for (auto& i : items) |
| 363 | { |
| 364 | if (i.type == Operator) |
| 365 | { |
| 366 | if (pending.size() == 1) |
| 367 | result.push_back(pending[0]); |
| 368 | else if (!pending.empty()) |
| 369 | result.push_back(Item {Group, pending, {}, 0}); |
| 370 | result.push_back(i); |
| 371 | pending.clear(); |
| 372 | hasOperators = true; |
| 373 | continue; |
| 374 | } |
| 375 | |
| 376 | if (i.type == StartOfContainer && pending.empty()) |
| 377 | { |
| 378 | result.push_back(i); |
| 379 | } |
| 380 | else if (i.type == EndOfContainer && hasOperators && pending.size() > 1) |
| 381 | { |
| 382 | result.push_back(Item {Group, pending, {}, 0}); |
| 383 | result.push_back(i); |
| 384 | pending.clear(); |
| 385 | } |
| 386 | else |
| 387 | { |
| 388 | pending.push_back(Item {i.type, CreateOperatorGroups(i.items), i.tokens, 0}); |
| 389 | } |
| 390 | } |
| 391 | |
| 392 | if (!pending.empty()) |
| 393 | { |
| 394 | if (hasOperators && pending.size() > 1) |
| 395 | result.push_back(Item {Group, pending, {}, 0}); |
| 396 | else |
| 397 | result.insert(result.end(), pending.begin(), pending.end()); |
| 398 | } |
| 399 | |
| 400 | return result; |
| 401 | } |
| 402 | |
| 403 | |
| 404 | static vector<Item> CreateOperatorPrecedenceGroups(const vector<Item>& items) |