symfony - How to check if array has more elements in twigs for loop? -

i concatenating array elements in single variable , between them. i'm getting record this

abc,def,ghi,  

i dont want add comma , after last element. code is:

{% driver in item.vehicles if driver.driver.firstname %} {% set isdriver = 1 %} {% set driverlist = driverlist ~ driver.driver.firstname ~ ',' %} {% endfor %}   

you can use twig loop variable needed this:

{% driver in item.vehicles if driver.driver.firstname %} {% set isdriver = 1 %} {% set driverlist = driverlist ~ driver.driver.firstname  %}     {% if loop.last == false %}    {% set driverlist = driverlist ~  ',' %}    {% endif %}  {% endfor %}