destruct object when is popped from bison stack?

[Jakub M]

Hi

I allocate a new object for each token, and i would like to delete the
object when the token is not used anymore. Is there any directive that
would run the delete code every time a token is popped from the stack?
I thought %destructor is the one, but now I am not sure... Exemplary
code below/

%union{
    char * sval;
    Variable * vval;
}

%token VARIABLE
%token Literal
%type <vval> Expression VARIABLE
%type <sval> Literal

%destructor { delete $$; } <vval>
%destructor { delete $$; } Literal