| 12 | { |
| 13 | public: |
| 14 | class Iterator |
| 15 | { |
| 16 | public: |
| 17 | Iterator & Move(UniChar c) |
| 18 | { |
| 19 | if (Rejects()) |
| 20 | return *this; |
| 21 | |
| 22 | if (Accepts()) |
| 23 | { |
| 24 | auto currentIt = m_it; |
| 25 | currentIt.Move(c); |
| 26 | |
| 27 | // While moving m_it, errors number decreases while matching unmatched symbols: |
| 28 | // source: a b c d e f |
| 29 | // query: a b c d e f |
| 30 | // errors: 5 4 3 2 1 0 |
| 31 | // |
| 32 | // After a misprinted symbol errors number remains the same: |
| 33 | // source: a b c d e f |
| 34 | // query: a b z d e f |
| 35 | // errors: 5 4 3 3 2 1 |
| 36 | // |
| 37 | // source: a b c d e f |
| 38 | // query: a b d c e f |
| 39 | // errors: 5 4 3 3 2 1 |
| 40 | // |
| 41 | // source: a b c d e f |
| 42 | // query: a b d e f |
| 43 | // errors: 5 4 3 3 2 |
| 44 | // |
| 45 | // source: a b c d e f |
| 46 | // query: a b c z d e f |
| 47 | // errors: 5 4 3 3 3 2 1 |
| 48 | // |
| 49 | // Errors number cannot decrease after it has increased once. |
| 50 | |
| 51 | if (currentIt.ErrorsMade() > ErrorsMade()) |
| 52 | return *this; |
| 53 | } |
| 54 | |
| 55 | m_it.Move(c); |
| 56 | if (m_it.Accepts()) |
| 57 | m_accepts = true; |
| 58 | |
| 59 | return *this; |
| 60 | } |
| 61 | |
| 62 | bool Accepts() const { return m_accepts; } |
| 63 | bool Rejects() const { return !Accepts() && m_it.Rejects(); } |
| 64 | size_t ErrorsMade() const { return m_it.ErrorsMade(); } |
| 65 | size_t PrefixErrorsMade() const { return m_it.PrefixErrorsMade(); } |
| 66 | |
| 67 | private: |
| 68 | friend class PrefixDFAModifier; |
| 69 | |
| 70 | Iterator(typename DFA::Iterator it) : m_it(it), m_accepts(m_it.Accepts()) {} |
| 71 |
no test coverage detected