let compile_let_decl d =
{
Formula.d_section = d.Formula.d_section ;
Formula.d_name = d.Formula.d_name ;
Formula.d_title = d.Formula.d_title ;
Formula.d_descr = d.Formula.d_descr ;
Formula.d_source = d.Formula.d_source ;
Formula.d_item = compile_let_item d.Formula.d_item ;
}