Function AR_DEDUP

src/arithmetic/list_funcs/list_funcs.c:662–694

given a list, return a similar list after removing duplicate elements order is preserved, duplicates are removed from the end of the list list.dedup(list) -> list list.dedup([1,2,1,3,3]) -> [1,2,3]

// list.dedup(list) -> list
// list.dedup([1,2,1,3,3]) -> [1,2,3]
SIValue AR_DEDUP(SIValue *argv, int argc, void *private_data) {
	SIValue list = argv[0];
	if(SI_TYPE(list) == T_NULL) {
		return SI_NullVal();
	}

	uint32_t n          = SIArray_Length(list);
	SIValue  dedup_list = SI_Array(n);

	dict *values = HashTableCreate(&def_dt);
	// check if value already exists in list
	for(uint i = 0; i < n; i++) {
		SIValue val = SIArray_Get(list, i);
		// initialize the hash state
		XXH64_state_t state;
		XXH_errorcode res = XXH64_reset(&state, 0);
		ASSERT(res != XXH_ERROR);

		SIValue_HashUpdate(val, &state);

		// finalize the hash
		XXH64_hash_t hash = XXH64_digest(&state);
		dictEntry *existing;
		dictEntry *entry = HashTableAddRaw(values, (void *)hash, &existing);
		if(existing == NULL) {
			SIArray_Append(&dedup_list, val);
		}
	}

	HashTableRelease(values);

	return dedup_list;
}

SIValue AR_REDUCE
(