<?php
$categoria = new Categoria("teste");
echo cadastrarCategoria($categoria);
 
function cadastrarCategoria($categoria) {
    $categoriaPai = $categoria->CategoriaPai ?? 'null';
    $query = "INSERT INTO categoria (nome, categoria_idcategoria) values ('{$categoria->Nome}', {$categoriaPai})";
    return $query;
}
 
class Categoria
{
    public $Nome;
    public $CategoriaPai;
 
    function __construct() 
    { 
        $a = func_get_args();
        $this->Nome = $a[0];
        $this->CategoriaPai = $a[1];
    }
} 

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