November 28, 2012 safety of move | ||||
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I find myself using [abusing?] move lately: import std.algorithm; import std.stdio; struct A { const(int) i; int j; int k; } void main() { A* a = new A(); // pretend this is malloc or something // *a = A(1) A a2 = A(1); move(a2, *a); A[] arr = new A[](2); //arr[1] = *a; move(*a, arr[1]); } For the first part, I have a A* pointing to uninitialized memory and I need to initialize it somehow. move works I guess because it uses memcpy or something. Not complaining, but wondering. The second part violates D's const semantics and maybe shouldn't be permitted. But it is. |
November 28, 2012 Re: safety of move | ||||
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Posted in reply to Ellery Newcomer | 11/28/2012 7:19 AM, Ellery Newcomer пишет: > I find myself using [abusing?] move lately: > > import std.algorithm; > import std.stdio; > > struct A { > const(int) i; > int j; > int k; > } > > void main() { > A* a = new A(); // pretend this is malloc or something > // *a = A(1) > A a2 = A(1); > move(a2, *a); > > A[] arr = new A[](2); > //arr[1] = *a; > move(*a, arr[1]); > } > > For the first part, I have a A* pointing to uninitialized memory and I > need to initialize it somehow. emplace should work for constructing A in a given chunk of memory. > move works I guess because it uses memcpy > or something. Not complaining, but wondering. > Yes it hacks through const/immutable at ease. The only requirement seems that it has to be shallow immutable/cont. > The second part violates D's const semantics and maybe shouldn't be > permitted. But it is. I agree. -- Dmitry Olshansky |
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