Files
ab_glyph_rasterizer
addr2line
adler
andrew
approx
arrayvec
ash
atom
backtrace
bitflags
byteorder
calloop
cfg_if
colorful
conrod_core
conrod_derive
conrod_example_shared
conrod_gfx
conrod_glium
conrod_piston
conrod_rendy
conrod_vulkano
conrod_wgpu
conrod_winit
copyless
copypasta
crossbeam
crossbeam_channel
crossbeam_deque
crossbeam_epoch
crossbeam_queue
crossbeam_utils
daggy
dlib
downcast_rs
draw_state
either
fixedbitset
float
fnv
futures
futures_channel
futures_core
futures_executor
futures_io
futures_macro
futures_sink
futures_task
futures_util
async_await
future
io
lock
sink
stream
task
fxhash
getrandom
gfx
gfx_backend_empty
gfx_backend_vulkan
gfx_core
gfx_descriptor
gfx_hal
gfx_memory
gimli
glium
glutin
glutin_egl_sys
glutin_glx_sys
graphics
half
hibitset
inplace_it
input
instant
interpolation
iovec
itoa
lazy_static
lazycell
libc
libloading
line_drawing
linked_hash_map
lock_api
log
maybe_uninit
memchr
memmap
memoffset
miniz_oxide
mio
mio_extras
naga
net2
nix
nom
num
num_bigint
num_complex
num_cpus
num_integer
num_iter
num_rational
num_traits
object
once_cell
ordered_float
ordermap
osmesa_sys
owned_ttf_parser
parking_lot
parking_lot_core
percent_encoding
petgraph
pin_project
pin_project_internal
pin_project_lite
pin_utils
ppv_lite86
proc_macro2
proc_macro_hack
proc_macro_nested
quote
rand
rand_chacha
rand_core
raw_window_handle
read_color
relevant
rendy
rendy_chain
rendy_command
rendy_core
rendy_descriptor
rendy_factory
rendy_frame
rendy_graph
rendy_init
rendy_memory
rendy_mesh
rendy_resource
rendy_shader
rendy_texture
rendy_wsi
rustc_demangle
rustc_hash
rusttype
ryu
same_file
scoped_tls
scopeguard
serde
serde_derive
serde_json
shaderc
shaderc_sys
shared_library
slab
smallvec
smithay_client_toolkit
smithay_clipboard
spirv_headers
stb_truetype
syn
takeable_option
texture
thiserror
thiserror_impl
thread_profiler
time
tracing
tracing_core
ttf_parser
typed_arena
unicode_xid
vecmath
viewport
vk_sys
void
vulkano
buffer
command_buffer
descriptor
device
framebuffer
image
instance
memory
pipeline
query
swapchain
sync
vulkano_shaders
walkdir
wayland_client
wayland_commons
wayland_cursor
wayland_egl
wayland_protocols
wayland_sys
wgpu
wgpu_core
wgpu_types
winit
x11
x11_clipboard
x11_dl
xcb
xcursor
xdg
xml
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
use core::fmt;
use core::pin::Pin;
use futures_core::future::{FusedFuture, Future, TryFuture};
use futures_core::stream::TryStream;
use futures_core::task::{Context, Poll};
use pin_project::pin_project;

/// Future for the [`try_fold`](super::TryStreamExt::try_fold) method.
#[pin_project]
#[must_use = "futures do nothing unless you `.await` or poll them"]
pub struct TryFold<St, Fut, T, F> {
    #[pin]
    stream: St,
    f: F,
    accum: Option<T>,
    #[pin]
    future: Option<Fut>,
}

impl<St, Fut, T, F> fmt::Debug for TryFold<St, Fut, T, F>
where
    St: fmt::Debug,
    Fut: fmt::Debug,
    T: fmt::Debug,
{
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("TryFold")
            .field("stream", &self.stream)
            .field("accum", &self.accum)
            .field("future", &self.future)
            .finish()
    }
}

impl<St, Fut, T, F> TryFold<St, Fut, T, F>
where St: TryStream,
      F: FnMut(T, St::Ok) -> Fut,
      Fut: TryFuture<Ok = T, Error = St::Error>,
{
    pub(super) fn new(stream: St, f: F, t: T) -> TryFold<St, Fut, T, F> {
        TryFold {
            stream,
            f,
            accum: Some(t),
            future: None,
        }
    }
}

impl<St, Fut, T, F> FusedFuture for TryFold<St, Fut, T, F>
    where St: TryStream,
          F: FnMut(T, St::Ok) -> Fut,
          Fut: TryFuture<Ok = T, Error = St::Error>,
{
    fn is_terminated(&self) -> bool {
        self.accum.is_none() && self.future.is_none()
    }
}

impl<St, Fut, T, F> Future for TryFold<St, Fut, T, F>
    where St: TryStream,
          F: FnMut(T, St::Ok) -> Fut,
          Fut: TryFuture<Ok = T, Error = St::Error>,
{
    type Output = Result<T, St::Error>;

    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
        let mut this = self.project();

        Poll::Ready(loop {
            if let Some(fut) = this.future.as_mut().as_pin_mut() {
                // we're currently processing a future to produce a new accum value
                let res = ready!(fut.try_poll(cx));
                this.future.set(None);
                match res {
                    Ok(a) => *this.accum = Some(a),
                    Err(e) => break Err(e),
                }
            } else if this.accum.is_some() {
                // we're waiting on a new item from the stream
                let res = ready!(this.stream.as_mut().try_poll_next(cx));
                let a = this.accum.take().unwrap();
                match res {
                    Some(Ok(item)) => this.future.set(Some((this.f)(a, item))),
                    Some(Err(e)) => break Err(e),
                    None => break Ok(a),
                }
            } else {
                panic!("Fold polled after completion")
            }
        })
    }
}