Reads the currently highest-ranked heap element during traversal.
The examples focus on the operation itself, including the important distinction: top peeks without moving the iterator or removing an element.
What It Does
Use the examples below to observe the behavior on a small dataset before extending it to application code.
Syntax and Return Value
SplHeap::current()
The displayed signature describes the API or identifies any correction or optional dependency. When a parameter is optional, supply it only when the task requires it.
Example 1: Basic Use
SplMaxHeap is used because the abstract SplHeap cannot be instantiated. The current call is shown on a small, inspectable dataset.
<?php
$heap = new SplMaxHeap();
$heap->insert(4);
$heap->insert(12);
$heap->insert(7);
$heap->rewind();
echo json_encode($heap->current());
Output from a successful local PHP 8.4 run:
12
Example 2: Checking Behavior
SplMaxHeap is used because the abstract SplHeap cannot be instantiated. The current call is shown on a small, inspectable dataset.
<?php
$heap = new SplMaxHeap();
$heap->insert(2);
$heap->insert(9);
$heap->insert(5);
$heap->insert(1);
$heap->rewind();
echo json_encode($heap->current());
Output from a successful local PHP 8.4 run:
9
Example 3: Practical Example
SplMaxHeap is used because the abstract SplHeap cannot be instantiated. The current call is shown on a small, inspectable dataset.
<?php
$heap = new SplMaxHeap();
$heap->insert(19);
$heap->insert(3);
$heap->insert(11);
$heap->rewind();
echo json_encode($heap->current());
Output from a successful local PHP 8.4 run:
19
Important Behavior and Edge Cases
SplHeap is abstract; use SplMaxHeap/SplMinHeap or implement compare.
Comparison with Related Approaches
| Approach | Difference |
|---|---|
| SplHeap::current | Reads the currently highest-ranked heap element during traversal. |
| Related API or alternative | top peeks without moving the iterator or removing an element. |
Common Beginner Mistakes
| Mistake | Correct approach |
|---|---|
| Ignoring the operation-specific limits | SplHeap is abstract; use SplMaxHeap/SplMinHeap or implement compare. |
| Confusing it with a related API | top peeks without moving the iterator or removing an element. |
Key Takeaways
- Reads the currently highest-ranked heap element during traversal.
- SplHeap is abstract; use SplMaxHeap/SplMinHeap or implement compare.
- top peeks without moving the iterator or removing an element.
Use SplHeap::current when its documented behavior matches the problem. Test the relevant edge cases in your own runtime before deploying it.