Current user is...

index.php

<?php
$current_user = wp_get_current_user();

if (isset($current_user->caps['administrator'])) {
    echo 'Olá administrador';
}

if (isset($current_user->caps['editor'])) {
    echo 'Olá editor';
}

if (isset($current_user->caps['author'])) {
    echo 'Olá autor';
}

if (isset($current_user->caps['contributor'])) {
    echo 'Olá colaborador';
}

if (isset($current_user->caps['subscriber'])) {
    echo 'Olá assinante';
}

?>