ScopedAllocator
delegates all allocation requests to ParentAllocator
. When destroyed, the ScopedAllocator
object automatically calls deallocate
for all memory allocated through its lifetime. (The deallocateAll
function is also implemented with the same semantics.)
deallocate
is also supported, which is where most implementation effort and overhead of ScopedAllocator
go. If deallocate
is not needed, a simpler design combining AllocatorList
with Region
is recommended.
import std.experimental.allocator.mallocator : Mallocator; import std.typecons : Ternary; ScopedAllocator!Mallocator alloc; writeln(alloc.empty); // Ternary.yes const b = alloc.allocate(10); writeln(b.length); // 10 writeln(alloc.empty); // Ternary.no
If ParentAllocator
is stateful, parent
is a property giving access to an AffixAllocator!ParentAllocator
. Otherwise, parent
is an alias for AffixAllocator!ParentAllocator.instance
.
Alignment offered
Forwards to parent.goodAllocSize
(which accounts for the management overhead).
Allocates memory. For management it actually allocates extra memory from the parent.
Forwards to parent.expand(b, delta)
.
Reallocates b
to new size s
.
Forwards to parent.owns(b)
.
Deallocates b
.
Deallocates all memory allocated.
Returns Ternary.yes
if this allocator is not responsible for any memory, Ternary.no
otherwise. (Never returns Ternary.unknown
.)
© 1999–2019 The D Language Foundation
Licensed under the Boost License 1.0.
https://dlang.org/phobos/std_experimental_allocator_building_blocks_scoped_allocator.html