Returns the previous item appearing in the list passed as an input argument. This function can be applied to lists containing stm_list_id_elm’s.Note that “previous” refers to the item physically located before the current item in the list. The “current” item is determined using the utility functionstm_list_last_id_element
.
Input/Output Items in the input list must be stm_list_id_elm’s. In the list of statesS1
,S2
,S3
, andS4
(appearing in this order) assigned to the variablestate_list,
locate the stateS4
by callingstm_list_last_ids_element;
S4
becomes the current item. To find the previous element in the list, use the following statements:stm_list state_list;
stm_id state_id;
int status;
.
.
state_id = (stm_id) stm_list_last_element (
state_list, &status);
state_id = (stm_id) stm_list_previous_id_element (
state_list, &status);
printf ("State of interest is: %s\n",
stm_r_st_name (state_id, &status));
.
.This function can be used in afor
loop (in conjunction withstm_list_last_id_element
) to perform operations on all elements in the list in reverse order.