Hi,

[I'm trying to share some of my thoughts about intarray contrib module.
If this is the wrong way to achieve this, please warn me. (Should I
first get in touch with Teodor Sigaev and Oleg Bartunov?)]

[6]
_int_same() in _int_op.c looks like making some redundant sorting and
not taking advantage of sorted arrays while comparing each other. Here's
the related code piece:

SORT(a);
SORT(b);
na = ARRNELEMS(a);
nb = ARRNELEMS(b);
da = ARRPTR(a);
db = ARRPTR(b);

result = FALSE;

if (na == nb)
{
result = TRUE;
for (n = 0; n < na; n++)
if (da[n] != db[n])
{
result = FALSE;
break;
}
}

IMHO, SORT() macro should be called after "if (na == nb)" block. (SORT()
doesn't remove duplicates.) Also, in the inner block, while comparing
two arrays, we can take advantage of sorting of arrays. While current
behaviour is like

if (A[0] == B[0] && A[1] == B[1] && ...)

we can replace it with sth like

if (A[0] == B[0] && A[ N] == B[ N] &&
A[1] == B[1] && A[N-1] == B[N-1] &&
...)

Attached patch tries to implement both behaviours mentioned above and
some minor hacking for arrays of 1,2 and 3 items.


Regards.


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