emplace

Constructs a new object of type T in memory with the given arguments.

If T is a $(D_KEYWORD class), emplace returns a class reference of type T, otherwise a pointer to the constructed object is returned.

If T is a nested class inside another class, outer should be an instance of the outer class.

args are arguments for the constructor of T. If T isn't an aggregate type and doesn't have a constructor, memory can be initialized to args[0] if Args.length == 1, Args[0] should be implicitly convertible to T then.

T emplace(void[] memory, U outer, Args args)
T emplace(void[] memory, Args args)
T* emplace(void[] memory, Args args)
T* emplace(void[] memory, Args args)
T*
emplace
(
T
Args...
)
(
void[] memory
,
auto ref Args args
)
if (
!isPolymorphicType!T &&
isAggregateType!T
)
out (result) { assert (memory.ptr is result); }
void initializeOne(void[] memory, T* result)

Parameters

T: Constructed type.
Args: Types of the constructor arguments if T has a constructor or the type of the initial value.
args Args: Constructor arguments if T has a constructor or the initial value.

Return Value

Type: T*

New instance of type T constructed in memory.

Precondition: memory.length == stateSize!T. Postcondition: memory and the result point to the same memory.

Examples

ubyte[4] memory;

auto i = emplace!int(memory);
static assert(is(typeof(i) == int*));
assert(*i == 0);

i = emplace!int(memory, 5);
assert(*i == 5);

static struct S
{
    int i;
    @disable this();
    @disable this(this);
    this(int i) @nogc nothrow pure @safe
    {
        this.i = i;
    }
}
auto s = emplace!S(memory, 8);
static assert(is(typeof(s) == S*));
assert(s.i == 8);

emplace

Parameters

Return Value

Examples

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