val cast_to_i_var : [< nf > `I `Var] -> i_var
val cast_to_i_n_var : [< nf > `I `N `Var] -> i_n_var
val cast_to_i_num_var : [< nf > `I `N `Match `Var] -> i_num_var
val cast_to_i_var : [< nf > `I `Var] -> i_var
val cast_to_i_n_var : [< nf > `I `N `Var] -> i_n_var
val cast_to_i_num_var : [< nf > `I `N `Match `Var] -> i_num_var