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#' @include arrow-package.R
#'
#' @title class arrow::MemoryPool
#'
#' @usage NULL
#' @format NULL
#' @docType class
#'
#' @section Methods:
#'
#' - `backend_name`: one of "jemalloc", "mimalloc", or "system". Alternative
#'   memory allocators are optionally enabled at build time. Windows builds
#'   generally have `mimalloc`, and most others have both `jemalloc` (used by
#'   default) and `mimalloc`. To change memory allocators at runtime, set the
#'   environment variable `ARROW_DEFAULT_MEMORY_POOL` to one of those strings
#'   prior to loading the `arrow` library.
#' - `bytes_allocated`
#' - `max_memory`
#'
#' @rdname MemoryPool
#' @name MemoryPool
#' @keywords internal
MemoryPool <- R6Class("MemoryPool",
  inherit = ArrowObject,
  public = list(
    # TODO: Allocate
    # TODO: Reallocate
    # TODO: Free
  ),
  active = list(
    backend_name = function() MemoryPool__backend_name(self),
    bytes_allocated = function() MemoryPool__bytes_allocated(self),
    max_memory = function() MemoryPool__max_memory(self)
  )
)

#' Arrow's default [MemoryPool]
#'
#' @return the default [MemoryPool]
#' @export
#' @keywords internal
default_memory_pool <- function() {
  MemoryPool__default()
}