What's the best annotation to describe a simulation overload function? - php

Question

I am using Visual Studio Code(VS Code), it can display the annotation of functios.
I am try to improve write a PHPDoc standard.
Can any suggestions to me? Thank you.
Here have 3 functions, but they are not the focal point .
I just want to know how to write a PHPDoc standard describe the function 2 and simulation overload function 3.
Ref:
https://github.com/phpDocumentor/fig-standards/blob/master/proposed/phpdoc.md#54-examples
<?php
// Function 1:
/**
* Check if A is equal to B.(Just a sample note, not important)
*
* #param string A
* #param string B
*
* #return bool
*/
function checkAandB_1($a, $b){
if($a === $b)
return true;
return false;
}
// Function 2:
/**
* Check if A is equal to B.(Just a sample note, not important)
*
* #param string Input x,y (<=here, I need to known how to write a right note to describe this function can support input a string combin x and y with a comma in one line)
*
* #return bool
*/
function checkAandB_2($str){
if( substr_count($str, ",") === 1 ) {
$strArr = explode(",",$str);
if($strArr[0] === $strArr[1])
return true;
}
return false;
}
// Function 3: Simulation a overload function
/**
* Check if A is equal to B.(Just a sample note, not important)
*
* #param string (What's the best annotation to describe this function?)
*
* #return bool
*/
function checkAandB_overload($str, $b = null){
if(isset($b) && $str === $b){
return true;
}elseif( substr_count($str, ",") === 1 ) {
$strArr = explode(",",$str);
if($strArr[0] === $strArr[1])
return true;
}
return false;
}
var_dump(checkAandB_1("1","2")); // false
var_dump(checkAandB_1("2","2")); // true
var_dump(checkAandB_2("1,2")); // false
var_dump(checkAandB_2("2,2")); // true
var_dump(checkAandB_overload("1","2")); // false
var_dump(checkAandB_overload("2","2")); // true
var_dump(checkAandB_overload("1,2")); // false
var_dump(checkAandB_overload("2,2")); // true