On Tuesday, 29 October 2013 at 11:26:45 UTC, Froglegs wrote:
BigInt n = 100;
n += 10;
++n;
... and both the 2nd and 3rd lines will result in a
reallocation even though there is no need for it, because only
n is referencing the memory it wraps.
Does BigInt not have overloaded operators for adding normal
integers? Is it converting 10 to a BigInt prior to adding it to
n?
Yes, it has overloaded operators, but that's not relevant. The
issue is that
initially n points to an block of memory, containing [100].
Then, if you use COW, n+= 10 isn't in-place. It has to create a
new array, containing [110].
Then ++n creates a third array. [111].
