module payload_m implicit none private public :: payload_t, empty_payload type :: payload_t !! A raw buffer to facilitate data transfer between images !! !! Facilitates view of the data as either a string or raw bytes. !! Typical usage will be either to !! * produce a string representation of the data, and then parse that string to recover the original data !! * use the `transfer` function to copy the raw bytes of the data private integer, allocatable, public :: payload_(:) contains private procedure, public :: raw_payload procedure, public :: string_payload end type interface payload_t pure module function from_raw(payload) result(new_payload) implicit none integer, intent(in) :: payload(:) type(payload_t) :: new_payload end function pure module function from_string(payload) result(new_payload) implicit none character(len=*), intent(in) :: payload type(payload_t) :: new_payload end function module procedure empty_payload end interface interface pure module function empty_payload() implicit none type(payload_t) :: empty_payload end function pure module function raw_payload(self) implicit none class(payload_t), intent(in) :: self integer, allocatable :: raw_payload(:) end function pure module function string_payload(self) implicit none class(payload_t), intent(in) :: self character(len=:), allocatable :: string_payload end function end interface end module submodule(payload_m) payload_s implicit none contains module procedure from_raw new_payload%payload_ = payload end procedure module procedure from_string new_payload = payload_t([len(payload), transfer(payload,[integer::])]) end procedure module procedure empty_payload empty_payload%payload_ = [integer::] end procedure module procedure raw_payload if (allocated(self%payload_)) then raw_payload = self%payload_ else raw_payload = [integer::] end if end procedure module procedure string_payload if (allocated(self%payload_)) then if (size(self%payload_) > 0) then allocate(character(len=self%payload_(1)) :: string_payload) if (len(string_payload) > 0) & string_payload = transfer(self%payload_(2:),string_payload) else allocate(character(len=0) :: string_payload) end if else allocate(character(len=0) :: string_payload) end if end procedure end submodule program example use payload_m, only: payload_t character(len=*), parameter :: MESSAGE = "Hello, World!" type(payload_t) :: mailbox[*] if (this_image() == 1) then mailbox = payload_t(MESSAGE) end if sync all if (this_image() /= 1) then mailbox = mailbox[1] end if print *, mailbox%string_payload(), " from image: ", this_image() end program