On 12/18/2011 11:12 PM, RenatoL wrote:
Reading the book from Alexandrescu we can find this (page 103-104,
at least in my edition):
Expanding arrays has a couple of subtleties that concern possible
reallocation of the array. Consider:
auto a = [87, 40, 10, 2];
auto b = a; // Now a and b refer to the same chunk
a ~= [5, 17]; // Append to a
a[0] = 15; // Modify a[0]
assert(b[0] == 15); // Pass or fail?
it seems natural that the test is ok but it is not... if we read
more we find:
"D leaves~= the freedom of either expanding by reallocation or
opportunistically expanding in place if there is enough unused
memory at the end of the current array."
At a first glance this seems to be a serious issue... it seems hard
to accept that b can lost its connection to "a" in a silent mode due
to a reallocation
Is there a safe mode to do this for large arrays?
Assuming 'safe' means preserving aliasing: No. How would you implement
it? Anyway, this is not such a huge issue in practice. If you want
aliasing, just don't append to the slices.
