Remove and return the front item. Returns: The front element. Raises: IndexError: If the queue is empty.
(self)
| 174 | self._size += 1 |
| 175 | |
| 176 | def dequeue(self) -> object: |
| 177 | """Remove and return the front item. |
| 178 | |
| 179 | Returns: |
| 180 | The front element. |
| 181 | |
| 182 | Raises: |
| 183 | IndexError: If the queue is empty. |
| 184 | """ |
| 185 | if self.is_empty(): |
| 186 | raise IndexError("Queue is empty") |
| 187 | value = self._front.value |
| 188 | if self._front is self._rear: |
| 189 | self._front = None |
| 190 | self._rear = None |
| 191 | else: |
| 192 | self._front = self._front.next |
| 193 | self._size -= 1 |
| 194 | return value |
| 195 | |
| 196 | def peek(self) -> object: |
| 197 | """Return the front element without removing it. |