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slot_count ​

Summary. Return the number of elements in a slotted array (STI_ARRAY).

Signature.

c
int64_t slot_count(uint32_t slot);

Parameters.

NameTypeDescription
slotuint32_tSlot holding an array.

Return value. Returns the element count on success. Errors: DOESNT_EXIST (-5) if the slot is empty; INTERNAL_ERROR (-2) if corrupt; NOT_AN_ARRAY (-22) if the slotted object is not an STI_ARRAY.

Common failure patterns.

  • Calling it on a non-array slot (e.g. a plain object or leaf field) → NOT_AN_ARRAY.

Caveats / notes.

  • Pair with slot_subarray to iterate: slot_count gives the loop bound, and slot_subarray(parent, i, new) extracts element i.

Minimal example.

c
int64_t n = slot_count(arr_slot);

Practical example.

c
// Iterate a slotted array.
int64_t n = slot_count(arr_slot);
for (int i = 0; GUARD(256), i < n; ++i)
{
    uint32_t elem = slot_subarray(arr_slot, i, 0);
    // ... inspect elem ...
}

Related APIs. slot_subarray, slot_count.