1.2.985. Pre-increment¶
When possible, use the pre-increment operator (
++$ior--$i) instead of the post-increment operator ($i++or$i--).
The latter needs an extra memory allocation that costs about 10% of performances. This is a micro-optimisation. However, its usage is so widespread, including within loops, that it may eventually have an significant impact on execution time. As such, it is recommended to adopt this rule, and only consider changing legacy code as they are refactored for other reasons.
<?php
// ++$i should be preferred over $i++, as current value is not important
for($i = 0; $i <10; ++$i) {
// do Something
}
// ++$b and $b++ have different impact here, since $a will collect $b + 1 or $b, respectively.
$a = $b++;
?>
1.2.985.1. Suggestions¶
Use the pre increment when the new value is not reused.
1.2.985.2. Specs¶
Short name |
Performances/PrePostIncrement |
Rulesets |
|
Exakat since |
0.8.4 |
PHP Version |
All |
Severity |
Minor |
Time To Fix |
Quick (30 mins) |
Precision |
Very high |
Features |
increment |
Examples |
|
Available in |