On Thursday, 4 January 2018 at 11:05:25 UTC, tipdbmp wrote:
What is your definition of a dangling pointer?
A pointer pointing to freed memory, which presumably '&a[0]'
should be because it reallocates.
It allocates a larger array, but the old version is not freed up
front. Right because there might be live references to the old
data. Your pointer is such live reference. So while this pointer
references that old version of the array, it's not freed. Only
after no references are left the GC will make it free (and only
when next GC cycle happens, not immediately).
It seems that the '~=' operator "knows" that there's a
reference to 'a's old memory and it keeps it around instead of
freeing it.
It's just not its job to free that memory. That memory is freed
later by GC, when it's safe to do so.
