unfold_state.rs - source

Files

arrayvec

array_string.rs arrayvec.rs arrayvec_impl.rs char.rs errors.rs lib.rs utils.rs

async_attributes

async_channel

async_executor

async_global_executor

config.rs executor.rs init.rs lib.rs reactor.rs threading.rs

async_io

driver.rs lib.rs reactor.rs

async_lock

barrier.rs lib.rs mutex.rs rwlock.rs semaphore.rs

async_mutex

async_process

async_rustbus

conn

addr.rs ancillary.rs mod.rs recv.rs sender.rs

rustbus_core

message_builder

mod.rs path.rs standard_messages.rs

lib.rs routing.rs utils.rs

async_std

collections

binary_heap

extend.rs from_stream.rs mod.rs

btree_map

extend.rs from_stream.rs mod.rs

btree_set

extend.rs from_stream.rs mod.rs

hash_map

extend.rs from_stream.rs mod.rs

hash_set

extend.rs from_stream.rs mod.rs

linked_list

extend.rs from_stream.rs mod.rs

vec_deque

extend.rs from_stream.rs mod.rs

fs

future

future

delay.rs flatten.rs join.rs mod.rs race.rs try_join.rs try_race.rs

into_future.rs maybe_done.rs mod.rs pending.rs poll_fn.rs ready.rs timeout.rs

io

net

tcp

listener.rs mod.rs stream.rs

udp

option

from_stream.rs mod.rs product.rs sum.rs

os

unix

net

datagram.rs listener.rs mod.rs stream.rs

fs.rs io.rs mod.rs

path

ancestors.rs components.rs iter.rs mod.rs path.rs pathbuf.rs

pin

result

from_stream.rs mod.rs product.rs sum.rs

rt

stream

string

extend.rs from_stream.rs mod.rs

sync

condvar.rs mod.rs waker_set.rs

task

block_on.rs builder.rs current.rs join_handle.rs mod.rs ready.rs sleep.rs spawn.rs spawn_blocking.rs spawn_local.rs task.rs task_id.rs task_local.rs task_locals_wrapper.rs yield_now.rs

unit

extend.rs from_stream.rs mod.rs

vec

extend.rs from_stream.rs mod.rs

channel.rs lib.rs macros.rs prelude.rs process.rs utils.rs

async_task

header.rs lib.rs raw.rs runnable.rs state.rs task.rs utils.rs

atomic_waker

bitflags

blocking

cache_padded

cfg_if

concurrent_queue

bounded.rs lib.rs single.rs unbounded.rs

crossbeam_utils

atomic

atomic_cell.rs consume.rs mod.rs seq_lock.rs

sync

mod.rs parker.rs sharded_lock.rs wait_group.rs

backoff.rs cache_padded.rs lib.rs thread.rs

ctor

derive_utils

ast.rs lib.rs parse.rs utils.rs

event_listener

fastrand

find_crate

error.rs lib.rs

futures

futures_channel

mpsc

mod.rs queue.rs sink_impl.rs

lib.rs lock.rs oneshot.rs

futures_core

task

__internal

atomic_waker.rs mod.rs

future.rs lib.rs stream.rs

futures_enum

futures_executor

enter.rs lib.rs local_pool.rs

futures_io

futures_lite

future.rs io.rs lib.rs prelude.rs stream.rs

futures_macro

executor.rs join.rs lib.rs select.rs

futures_sink

futures_task

arc_wake.rs future_obj.rs lib.rs noop_waker.rs spawn.rs waker.rs waker_ref.rs

futures_util

async_await

join_mod.rs mod.rs pending.rs poll.rs random.rs select_mod.rs

future

io

lock

bilock.rs mod.rs mutex.rs

sink

buffer.rs close.rs drain.rs err_into.rs fanout.rs feed.rs flush.rs map_err.rs mod.rs send.rs send_all.rs unfold.rs with.rs with_flat_map.rs

stream

abortable.rs empty.rs futures_ordered.rs iter.rs mod.rs once.rs pending.rs poll_fn.rs repeat.rs repeat_with.rs select.rs select_all.rs unfold.rs

task

mod.rs spawn.rs

abortable.rs fns.rs lib.rs never.rs unfold_state.rs

kv_log_macro

lazy_static

inline_lazy.rs lib.rs

libc

unix

linux_like

linux

arch

generic

gnu

b64

x86_64

align.rs mod.rs not_x32.rs

align.rs mod.rs

align.rs mod.rs

align.rs mod.rs

fixed_width_ints.rs lib.rs macros.rs

log

kv

error.rs key.rs mod.rs source.rs value.rs

lib.rs macros.rs

memchr

memchr

x86

avx.rs mod.rs sse2.rs

fallback.rs iter.rs mod.rs naive.rs

memmem

prefilter

x86

avx.rs mod.rs sse.rs

fallback.rs genericsimd.rs mod.rs

x86

avx.rs mod.rs sse.rs

byte_frequencies.rs genericsimd.rs mod.rs rabinkarp.rs rarebytes.rs twoway.rs util.rs vector.rs

nix

num_cpus

lib.rs linux.rs

once_cell

imp_std.rs lib.rs race.rs

parking

pin_project_lite

pin_utils

lib.rs projection.rs stack_pin.rs

polling

epoll.rs lib.rs

proc_macro2

detection.rs fallback.rs lib.rs marker.rs parse.rs wrapper.rs

proc_macro_hack

error.rs iter.rs lib.rs parse.rs quote.rs

proc_macro_nested

quote

ext.rs format.rs ident_fragment.rs lib.rs runtime.rs spanned.rs to_tokens.rs

rustable

gatt

server

chrc.rs descriptor.rs mod.rs one_time.rs service.rs

client.rs mod.rs

advertising.rs introspect.rs lib.rs properties.rs

rustbus

rustbus_derive

serde

de

ignored_any.rs impls.rs mod.rs seed.rs utf8.rs value.rs

private

de.rs doc.rs mod.rs ser.rs size_hint.rs

ser

fmt.rs impls.rs impossible.rs mod.rs

integer128.rs lib.rs macros.rs

signal_hook

iterator

exfiltrator

backend.rs mod.rs

low_level

channel.rs mod.rs pipe.rs signal_details.rs

signal_hook_registry

half_lock.rs lib.rs

slab

socket2

sys

lib.rs sockaddr.rs socket.rs sockref.rs

syn

toml

datetime.rs de.rs lib.rs macros.rs map.rs ser.rs spanned.rs tokens.rs value.rs

unicode_xid

lib.rs tables.rs

value_bag

internal

cast

mod.rs primitive.rs

error.rs fill.rs impls.rs lib.rs visit.rs

void

waker_fn

xml

use core::pin::Pin;

use pin_project_lite::pin_project;

pin_project! {
    /// UnfoldState used for stream and sink unfolds
    #[project = UnfoldStateProj]
    #[project_replace = UnfoldStateProjReplace]
    #[derive(Debug)]
    pub(crate) enum UnfoldState<T, R> {
        Value {
            value: T,
        },
        Future {
            #[pin]
            future: R,
        },
        Empty,
    }
}

impl<T, R> UnfoldState<T, R> {
    pub(crate) fn project_future(self: Pin<&mut Self>) -> Option<Pin<&mut R>> {
        match self.project() {
            UnfoldStateProj::Future { future } => Some(future),
            _ => None,
        }
    }

    pub(crate) fn take_value(self: Pin<&mut Self>) -> Option<T> {
        match &*self {
            UnfoldState::Value { .. } => match self.project_replace(UnfoldState::Empty) {
                UnfoldStateProjReplace::Value { value } => Some(value),
                _ => unreachable!(),
            },
            _ => None,
        }
    }
}