Unused parameters are misleading. Whatever the value passed to such parameters is, the behavior will be the same.
function doSomething($a, $b) { // "$a" is unused
return compute($b);
}
function doSomething($b) {
return compute($b);
}
Functions in classes that override a class or implement interfaces are ignored.
class C extends B {
function doSomething($a, $b) { // no issue reported on $b
compute($a);
}
}