Up: Index Samples [Index]
Indexes may be traversed by keys. Starting from the first to the last:
integer j; index i;
...
if (i_first(i, j)) {
do {
...
} while (isk_greater(i, j, j)); }
Or:
for (j in i) {
...
}
Starting from the last, backwards:
integer j; index i;
...
if (i_last(i, j)) {
do {
...
} while (isk_less(i, j, j)); }
Traversing may be started at any point.
Traversing an index mapping integers for integers and starting at 1001:
integer j;
index i;
j = 1001;
if (isk_upper(i, j, j)) {
integer a;
a = i[j];
do {
o_form("~: ~\n", j, a);
} while (is_g_integer(a, i, j, j));
}
Traversing indexes is also possible by traversal functions.
Displaying the keys and associated data for an index i, with a colon and a space in between:
i_wcall(i, o_, 0, -2, ": ", "\n");
The function will see ‘o_’ called for each index element with four arguments: the key (inserted in first position – ‘0’), the colon space string, the associated data in between (before the last position – ‘-2’) and the newline string.
The same, with a ‘for’ statement:
integer a, j;
index i;
for (j, a in i) {
o_form("~: ~\n", j, a);
}
See Index Statements.
See The For Statement.