pub struct BorrowedCursor<'a> { /* private fields */ }core_io_borrowed_buf)std only.Expand description
A writeable view of the unfilled portion of a BorrowedBuf.
The unfilled portion consists of an initialized and an uninitialized part; see BorrowedBuf
for details.
Data can be written directly to the cursor by using append or
indirectly by getting a slice of part or all of the cursor and writing into the slice. In the
indirect case, the caller must call advance after writing to inform
the cursor how many bytes have been written.
Once data is written to the cursor, it becomes part of the filled portion of the underlying
BorrowedBuf and can no longer be accessed or re-written by the cursor. I.e., the cursor tracks
the unfilled part of the underlying BorrowedBuf.
The lifetime 'a is a bound on the lifetime of the underlying buffer (which means it is a bound
on the data in that buffer by transitivity).
Implementations§
Source§impl<'a> BorrowedCursor<'a>
impl<'a> BorrowedCursor<'a>
Sourcepub fn reborrow<'this>(&'this mut self) -> BorrowedCursor<'this> ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub fn reborrow<'this>(&'this mut self) -> BorrowedCursor<'this> ⓘ
core_io_borrowed_buf)Reborrows this cursor by cloning it with a smaller lifetime.
Since a cursor maintains unique access to its underlying buffer, the borrowed cursor is not accessible while the new cursor exists.
Sourcepub fn capacity(&self) -> usize ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub fn capacity(&self) -> usize ⓘ
core_io_borrowed_buf)Returns the available space in the cursor.
Sourcepub fn written(&self) -> usize ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub fn written(&self) -> usize ⓘ
core_io_borrowed_buf)Returns the number of bytes written to this cursor since it was created from a BorrowedBuf.
Note that if this cursor is a reborrowed clone of another, then the count returned is the count written via either cursor, not the count since the cursor was reborrowed.
Sourcepub fn init_ref(&self) -> &[u8] ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub fn init_ref(&self) -> &[u8] ⓘ
core_io_borrowed_buf)Returns a shared reference to the initialized portion of the cursor.
Sourcepub fn init_mut(&mut self) -> &mut [u8] ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub fn init_mut(&mut self) -> &mut [u8] ⓘ
core_io_borrowed_buf)Returns a mutable reference to the initialized portion of the cursor.
Sourcepub fn uninit_mut(&mut self) -> &mut [MaybeUninit<u8>] ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub fn uninit_mut(&mut self) -> &mut [MaybeUninit<u8>] ⓘ
core_io_borrowed_buf)Returns a mutable reference to the uninitialized part of the cursor.
It is safe to uninitialize any of these bytes.
Sourcepub unsafe fn as_mut(&mut self) -> &mut [MaybeUninit<u8>] ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub unsafe fn as_mut(&mut self) -> &mut [MaybeUninit<u8>] ⓘ
core_io_borrowed_buf)Returns a mutable reference to the whole cursor.
§Safety
The caller must not uninitialize any bytes in the initialized portion of the cursor.
Sourcepub fn advance(&mut self, n: usize) -> &mut BorrowedCursor<'a> ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub fn advance(&mut self, n: usize) -> &mut BorrowedCursor<'a> ⓘ
core_io_borrowed_buf)Advances the cursor by asserting that n bytes have been filled.
After advancing, the n bytes are no longer accessible via the cursor and can only be
accessed via the underlying buffer. I.e., the buffer’s filled portion grows by n elements
and its unfilled portion (and the capacity of this cursor) shrinks by n elements.
If less than n bytes initialized (by the cursor’s point of view), set_init should be
called first.
§Panics
Panics if there are less than n bytes initialized.
Sourcepub unsafe fn advance_unchecked(&mut self, n: usize) -> &mut BorrowedCursor<'a> ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub unsafe fn advance_unchecked(&mut self, n: usize) -> &mut BorrowedCursor<'a> ⓘ
core_io_borrowed_buf)Advances the cursor by asserting that n bytes have been filled.
After advancing, the n bytes are no longer accessible via the cursor and can only be
accessed via the underlying buffer. I.e., the buffer’s filled portion grows by n elements
and its unfilled portion (and the capacity of this cursor) shrinks by n elements.
§Safety
The caller must ensure that the first n bytes of the cursor have been properly
initialised.
Sourcepub fn ensure_init(&mut self) -> &mut BorrowedCursor<'a> ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub fn ensure_init(&mut self) -> &mut BorrowedCursor<'a> ⓘ
core_io_borrowed_buf)Initializes all bytes in the cursor.
Sourcepub unsafe fn set_init(&mut self, n: usize) -> &mut BorrowedCursor<'a> ⓘ
🔬This is a nightly-only experimental API. (core_io_borrowed_buf)
pub unsafe fn set_init(&mut self, n: usize) -> &mut BorrowedCursor<'a> ⓘ
core_io_borrowed_buf)Asserts that the first n unfilled bytes of the cursor are initialized.
BorrowedBuf assumes that bytes are never de-initialized, so this method does nothing when
called with fewer bytes than are already known to be initialized.
§Safety
The caller must ensure that the first n bytes of the buffer have already been initialized.
Trait Implementations§
Source§impl<'a> Debug for BorrowedCursor<'a>
impl<'a> Debug for BorrowedCursor<'a>
Source§impl<'a> Write for BorrowedCursor<'a>
impl<'a> Write for BorrowedCursor<'a>
Source§fn write(&mut self, buf: &[u8]) -> Result<usize, Error> ⓘ
fn write(&mut self, buf: &[u8]) -> Result<usize, Error> ⓘ
Source§fn flush(&mut self) -> Result<(), Error> ⓘ
fn flush(&mut self) -> Result<(), Error> ⓘ
Source§fn is_write_vectored(&self) -> bool
fn is_write_vectored(&self) -> bool
can_vector)1.0.0 · Source§fn write_all(&mut self, buf: &[u8]) -> Result<(), Error> ⓘ
fn write_all(&mut self, buf: &[u8]) -> Result<(), Error> ⓘ
Source§fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error> ⓘ
fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error> ⓘ
write_all_vectored)Auto Trait Implementations§
impl<'a> Freeze for BorrowedCursor<'a>
impl<'a> RefUnwindSafe for BorrowedCursor<'a>
impl<'a> Send for BorrowedCursor<'a>
impl<'a> Sync for BorrowedCursor<'a>
impl<'a> Unpin for BorrowedCursor<'a>
impl<'a> !UnwindSafe for BorrowedCursor<'a>
Blanket Implementations§
§impl<T> ArchivePointee for T
impl<T> ArchivePointee for T
§type ArchivedMetadata = ()
type ArchivedMetadata = ()
§fn pointer_metadata(
_: &<T as ArchivePointee>::ArchivedMetadata,
) -> <T as Pointee>::Metadata
fn pointer_metadata( _: &<T as ArchivePointee>::ArchivedMetadata, ) -> <T as Pointee>::Metadata
Source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Source§impl<T> ByteSized for T
impl<T> ByteSized for T
Source§const BYTE_ALIGN: usize = _
const BYTE_ALIGN: usize = _
Source§fn byte_align(&self) -> usize ⓘ
fn byte_align(&self) -> usize ⓘ
Source§fn ptr_size_ratio(&self) -> [usize; 2]
fn ptr_size_ratio(&self) -> [usize; 2]
Source§impl<T, R> Chain<R> for Twhere
T: ?Sized,
impl<T, R> Chain<R> for Twhere
T: ?Sized,
§impl<T> ExecutableCommand for T
impl<T> ExecutableCommand for T
§fn execute(&mut self, command: impl Command) -> Result<&mut T, Error> ⓘ
fn execute(&mut self, command: impl Command) -> Result<&mut T, Error> ⓘ
Executes the given command directly.
The given command its ANSI escape code will be written and flushed onto Self.
§Arguments
-
The command that you want to execute directly.
§Example
use std::io;
use crossterm::{ExecutableCommand, style::Print};
fn main() -> io::Result<()> {
// will be executed directly
io::stdout()
.execute(Print("sum:\n".to_string()))?
.execute(Print(format!("1 + 1= {} ", 1 + 1)))?;
Ok(())
// ==== Output ====
// sum:
// 1 + 1 = 2
}Have a look over at the Command API for more details.
§Notes
- In the case of UNIX and Windows 10, ANSI codes are written to the given ‘writer’.
- In case of Windows versions lower than 10, a direct WinAPI call will be made.
The reason for this is that Windows versions lower than 10 do not support ANSI codes,
and can therefore not be written to the given
writer. Therefore, there is no difference between execute and queue for those old Windows versions.
Source§impl<T> ExtAny for T
impl<T> ExtAny for T
Source§fn as_any_mut(&mut self) -> &mut dyn Anywhere
Self: Sized,
fn as_any_mut(&mut self) -> &mut dyn Anywhere
Self: Sized,
Source§impl<T> ExtMem for Twhere
T: ?Sized,
impl<T> ExtMem for Twhere
T: ?Sized,
Source§const NEEDS_DROP: bool = _
const NEEDS_DROP: bool = _
Source§fn mem_align_of_val(&self) -> usize ⓘ
fn mem_align_of_val(&self) -> usize ⓘ
Source§fn mem_size_of_val(&self) -> usize ⓘ
fn mem_size_of_val(&self) -> usize ⓘ
Source§fn mem_needs_drop(&self) -> bool
fn mem_needs_drop(&self) -> bool
true if dropping values of this type matters. Read moreSource§fn mem_forget(self)where
Self: Sized,
fn mem_forget(self)where
Self: Sized,
self without running its destructor. Read moreSource§fn mem_replace(&mut self, other: Self) -> Selfwhere
Self: Sized,
fn mem_replace(&mut self, other: Self) -> Selfwhere
Self: Sized,
Source§unsafe fn mem_zeroed<T>() -> T
unsafe fn mem_zeroed<T>() -> T
unsafe_layout only.T represented by the all-zero byte-pattern. Read moreSource§unsafe fn mem_transmute_copy<Src, Dst>(src: &Src) -> Dst
unsafe fn mem_transmute_copy<Src, Dst>(src: &Src) -> Dst
unsafe_layout only.T represented by the all-zero byte-pattern. Read moreSource§fn mem_as_bytes(&self) -> &[u8] ⓘ
fn mem_as_bytes(&self) -> &[u8] ⓘ
unsafe_slice only.§impl<S> FromSample<S> for S
impl<S> FromSample<S> for S
fn from_sample_(s: S) -> S
Source§impl<T> Hook for T
impl<T> Hook for T
§impl<T> Instrument for T
impl<T> Instrument for T
§fn instrument(self, span: Span) -> Instrumented<Self> ⓘ
fn instrument(self, span: Span) -> Instrumented<Self> ⓘ
§fn in_current_span(self) -> Instrumented<Self> ⓘ
fn in_current_span(self) -> Instrumented<Self> ⓘ
Source§impl<T> IntoEither for T
impl<T> IntoEither for T
Source§fn into_either(self, into_left: bool) -> Either<Self, Self> ⓘ
fn into_either(self, into_left: bool) -> Either<Self, Self> ⓘ
self into a Left variant of Either<Self, Self>
if into_left is true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read moreSource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self> ⓘ
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self> ⓘ
self into a Left variant of Either<Self, Self>
if into_left(&self) returns true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read more§impl<F, T> IntoSample<T> for Fwhere
T: FromSample<F>,
impl<F, T> IntoSample<T> for Fwhere
T: FromSample<F>,
fn into_sample(self) -> T
§impl<T> LayoutRaw for T
impl<T> LayoutRaw for T
§fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError> ⓘ
fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError> ⓘ
§impl<T, N1, N2> Niching<NichedOption<T, N1>> for N2
impl<T, N1, N2> Niching<NichedOption<T, N1>> for N2
§unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool
unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool
§fn resolve_niched(out: Place<NichedOption<T, N1>>)
fn resolve_niched(out: Place<NichedOption<T, N1>>)
out indicating that a T is niched.§impl<T> Pointable for T
impl<T> Pointable for T
§impl<T> QueueableCommand for T
impl<T> QueueableCommand for T
§fn queue(&mut self, command: impl Command) -> Result<&mut T, Error> ⓘ
fn queue(&mut self, command: impl Command) -> Result<&mut T, Error> ⓘ
Queues the given command for further execution.
Queued commands will be executed in the following cases:
- When
flushis called manually on the given type implementingio::Write. - The terminal will
flushautomatically if the buffer is full. - Each line is flushed in case of
stdout, because it is line buffered.
§Arguments
-
The command that you want to queue for later execution.
§Examples
use std::io::{self, Write};
use crossterm::{QueueableCommand, style::Print};
fn main() -> io::Result<()> {
let mut stdout = io::stdout();
// `Print` will executed executed when `flush` is called.
stdout
.queue(Print("foo 1\n".to_string()))?
.queue(Print("foo 2".to_string()))?;
// some other code (no execution happening here) ...
// when calling `flush` on `stdout`, all commands will be written to the stdout and therefore executed.
stdout.flush()?;
Ok(())
// ==== Output ====
// foo 1
// foo 2
}Have a look over at the Command API for more details.
§Notes
- In the case of UNIX and Windows 10, ANSI codes are written to the given ‘writer’.
- In case of Windows versions lower than 10, a direct WinAPI call will be made.
The reason for this is that Windows versions lower than 10 do not support ANSI codes,
and can therefore not be written to the given
writer. Therefore, there is no difference between execute and queue for those old Windows versions.
§impl<W> SynchronizedUpdate for W
impl<W> SynchronizedUpdate for W
§fn sync_update<T>(
&mut self,
operations: impl FnOnce(&mut W) -> T,
) -> Result<T, Error> ⓘ
fn sync_update<T>( &mut self, operations: impl FnOnce(&mut W) -> T, ) -> Result<T, Error> ⓘ
Performs a set of actions within a synchronous update.
Updates will be suspended in the terminal, the function will be executed against self, updates will be resumed, and a flush will be performed.
§Arguments
-
Function
A function that performs the operations that must execute in a synchronized update.
§Examples
use std::io;
use crossterm::{ExecutableCommand, SynchronizedUpdate, style::Print};
fn main() -> io::Result<()> {
let mut stdout = io::stdout();
stdout.sync_update(|stdout| {
stdout.execute(Print("foo 1\n".to_string()))?;
stdout.execute(Print("foo 2".to_string()))?;
// The effects of the print command will not be present in the terminal
// buffer, but not visible in the terminal.
std::io::Result::Ok(())
})?;
// The effects of the commands will be visible.
Ok(())
// ==== Output ====
// foo 1
// foo 2
}§Notes
This command is performed only using ANSI codes, and will do nothing on terminals that do not support ANSI codes, or this specific extension.
When rendering the screen of the terminal, the Emulator usually iterates through each visible grid cell and renders its current state. With applications updating the screen a at higher frequency this can cause tearing.
This mode attempts to mitigate that.
When the synchronization mode is enabled following render calls will keep rendering the last rendered state. The terminal Emulator keeps processing incoming text and sequences. When the synchronized update mode is disabled again the renderer may fetch the latest screen buffer state again, effectively avoiding the tearing effect by unintentionally rendering in the middle a of an application screen update.