On Sat, 13 Nov 2010 15:57:50 -0500, spir <denis.s...@gmail.com> wrote:
On Fri, 12 Nov 2010 08:03:26 -0500
"Steven Schveighoffer" <schvei...@yahoo.com> wrote:
Essentially, if you change your line above to:
this.patterns = patterns.dup;
Works, but I don't understand why: isn't the duplicate also allocated on
the stack? I mean, dup is supposed to just duplicate, isn't it? what
does it give to the new structure that the original one hasn't? I
thought I would have to do for instance:
ints[] x;
void f(int[] ints...) {
x.length = ints.length; // allocate new area on the heap
x[] = ints[]; // copy elements in there
}
When doing this:
arr1 = arr2;
It copies the reference to the data, not the data itself. Since the data
is on the stack, you are still pointing at the stack
arr1 = arr2.dup;
copies the data itself, then returns a reference to the new data. The
reference is stored wherever the reference is stored. In your case, the
reference this.patterns is stored in the class, so it's also stored on the
heap.
I hope this is clearer.
-Steve
