Trait std::convert::From1.0.0[][src]

pub trait From<T> {
#[lang = "from"]    pub fn from(T) -> Self;
}

Used to do value-to-value conversions while consuming the input value. It is the reciprocal of Into.

One should always prefer implementing From over Into because implementing From automatically provides one with an implementation of Into thanks to the blanket implementation in the standard library.

Only implement Into when targeting a version prior to Rust 1.41 and converting to a type outside the current crate. From was not able to do these types of conversions in earlier versions because of Rust's orphaning rules. See Into for more details.

Prefer using Into over using From when specifying trait bounds on a generic function. This way, types that directly implement Into can be used as arguments as well.

The From is also very useful when performing error handling. When constructing a function that is capable of failing, the return type will generally be of the form Result<T, E>. The From trait simplifies error handling by allowing a function to return a single error type that encapsulate multiple error types. See the "Examples" section and the book for more details.

Note: This trait must not fail. If the conversion can fail, use TryFrom.

Generic Implementations

Examples

String implements From<&str>:

An explicit conversion from a &str to a String is done as follows:

let string = "hello".to_string();
let other_string = String::from("hello");

assert_eq!(string, other_string);
Run

While performing error handling it is often useful to implement From for your own error type. By converting underlying error types to our own custom error type that encapsulates the underlying error type, we can return a single error type without losing information on the underlying cause. The '?' operator automatically converts the underlying error type to our custom error type by calling Into<CliError>::into which is automatically provided when implementing From. The compiler then infers which implementation of Into should be used.

use std::fs;
use std::io;
use std::num;

enum CliError {
    IoError(io::Error),
    ParseError(num::ParseIntError),
}

impl From<io::Error> for CliError {
    fn from(error: io::Error) -> Self {
        CliError::IoError(error)
    }
}

impl From<num::ParseIntError> for CliError {
    fn from(error: num::ParseIntError) -> Self {
        CliError::ParseError(error)
    }
}

fn open_and_parse_file(file_name: &str) -> Result<i32, CliError> {
    let mut contents = fs::read_to_string(&file_name)?;
    let num: i32 = contents.trim().parse()?;
    Ok(num)
}
Run

Required methods

#[lang = "from"]pub fn from(T) -> Self[src]

Performs the conversion.

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Implementors

impl From<&'_ str> for Box<dyn Error>1.6.0[src]

fn from(err: &str) -> Box<dyn Error>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a str into a box of dyn Error.

Examples

use std::error::Error;
use std::mem;

let a_str_error = "a str error";
let a_boxed_error = Box::<dyn Error>::from(a_str_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))
Run

impl From<&'_ CStr> for Box<CStr>1.17.0[src]

impl From<&'_ CStr> for CString1.7.0[src]

impl From<&'_ CStr> for Rc<CStr>1.24.0[src]

impl From<&'_ CStr> for Arc<CStr>1.24.0[src]

impl From<&'_ OsStr> for Box<OsStr>1.17.0[src]

impl From<&'_ OsStr> for Rc<OsStr>1.24.0[src]

impl From<&'_ OsStr> for Arc<OsStr>1.24.0[src]

impl From<&'_ Path> for Box<Path>1.17.0[src]

impl From<&'_ Path> for Rc<Path>1.24.0[src]

fn from(s: &Path) -> Rc<Path>[src]

Converts a Path into an Rc by copying the Path data into a new Rc buffer.

impl From<&'_ Path> for Arc<Path>1.24.0[src]

fn from(s: &Path) -> Arc<Path>[src]

Converts a Path into an Arc by copying the Path data into a new Arc buffer.

impl From<Cow<'_, CStr>> for Box<CStr>1.45.0[src]

impl From<Cow<'_, OsStr>> for Box<OsStr>1.45.0[src]

impl From<Cow<'_, Path>> for Box<Path>1.45.0[src]

impl From<Infallible> for TryFromSliceError1.36.0[src]

impl From<Infallible> for TryFromIntError1.34.0[src]

impl From<ErrorKind> for Error1.14.0[src]

Intended for use for errors not exposed to the user, where allocating onto the heap (for normal construction via Error::new) is too costly.

fn from(kind: ErrorKind) -> Error[src]

Converts an ErrorKind into an Error.

This conversion allocates a new error with a simple representation of error kind.

Examples

use std::io::{Error, ErrorKind};

let not_found = ErrorKind::NotFound;
let error = Error::from(not_found);
assert_eq!("entity not found", format!("{}", error));
Run

impl From<[u8; 4]> for IpAddr1.17.0[src]

fn from(octets: [u8; 4]) -> IpAddr[src]

Creates an IpAddr::V4 from a four element byte array.

Examples

use std::net::{IpAddr, Ipv4Addr};

let addr = IpAddr::from([13u8, 12u8, 11u8, 10u8]);
assert_eq!(IpAddr::V4(Ipv4Addr::new(13, 12, 11, 10)), addr);
Run

impl From<[u8; 4]> for Ipv4Addr1.9.0[src]

fn from(octets: [u8; 4]) -> Ipv4Addr[src]

Creates an Ipv4Addr from a four element byte array.

Examples

use std::net::Ipv4Addr;

let addr = Ipv4Addr::from([13u8, 12u8, 11u8, 10u8]);
assert_eq!(Ipv4Addr::new(13, 12, 11, 10), addr);
Run

impl From<[u8; 16]> for IpAddr1.17.0[src]

fn from(octets: [u8; 16]) -> IpAddr[src]

Creates an IpAddr::V6 from a sixteen element byte array.

Examples

use std::net::{IpAddr, Ipv6Addr};

let addr = IpAddr::from([
    25u8, 24u8, 23u8, 22u8, 21u8, 20u8, 19u8, 18u8,
    17u8, 16u8, 15u8, 14u8, 13u8, 12u8, 11u8, 10u8,
]);
assert_eq!(
    IpAddr::V6(Ipv6Addr::new(
        0x1918, 0x1716,
        0x1514, 0x1312,
        0x1110, 0x0f0e,
        0x0d0c, 0x0b0a
    )),
    addr
);
Run

impl From<[u8; 16]> for Ipv6Addr1.9.0[src]

fn from(octets: [u8; 16]) -> Ipv6Addr[src]

Creates an Ipv6Addr from a sixteen element byte array.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::from([
    25u8, 24u8, 23u8, 22u8, 21u8, 20u8, 19u8, 18u8,
    17u8, 16u8, 15u8, 14u8, 13u8, 12u8, 11u8, 10u8,
]);
assert_eq!(
    Ipv6Addr::new(
        0x1918, 0x1716,
        0x1514, 0x1312,
        0x1110, 0x0f0e,
        0x0d0c, 0x0b0a
    ),
    addr
);
Run

impl From<[u16; 8]> for IpAddr1.17.0[src]

fn from(segments: [u16; 8]) -> IpAddr[src]

Creates an IpAddr::V6 from an eight element 16-bit array.

Examples

use std::net::{IpAddr, Ipv6Addr};

let addr = IpAddr::from([
    525u16, 524u16, 523u16, 522u16,
    521u16, 520u16, 519u16, 518u16,
]);
assert_eq!(
    IpAddr::V6(Ipv6Addr::new(
        0x20d, 0x20c,
        0x20b, 0x20a,
        0x209, 0x208,
        0x207, 0x206
    )),
    addr
);
Run

impl From<[u16; 8]> for Ipv6Addr1.16.0[src]

fn from(segments: [u16; 8]) -> Ipv6Addr[src]

Creates an Ipv6Addr from an eight element 16-bit array.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::from([
    525u16, 524u16, 523u16, 522u16,
    521u16, 520u16, 519u16, 518u16,
]);
assert_eq!(
    Ipv6Addr::new(
        0x20d, 0x20c,
        0x20b, 0x20a,
        0x209, 0x208,
        0x207, 0x206
    ),
    addr
);
Run

impl From<bool> for i81.28.0[src]

Converts a bool to a i8. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(i8::from(true), 1);
assert_eq!(i8::from(false), 0);
Run

impl From<bool> for i161.28.0[src]

Converts a bool to a i16. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(i16::from(true), 1);
assert_eq!(i16::from(false), 0);
Run

impl From<bool> for i321.28.0[src]

Converts a bool to a i32. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(i32::from(true), 1);
assert_eq!(i32::from(false), 0);
Run

impl From<bool> for i641.28.0[src]

Converts a bool to a i64. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(i64::from(true), 1);
assert_eq!(i64::from(false), 0);
Run

impl From<bool> for i1281.28.0[src]

Converts a bool to a i128. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(i128::from(true), 1);
assert_eq!(i128::from(false), 0);
Run

impl From<bool> for isize1.28.0[src]

Converts a bool to a isize. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(isize::from(true), 1);
assert_eq!(isize::from(false), 0);
Run

impl From<bool> for u81.28.0[src]

Converts a bool to a u8. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(u8::from(true), 1);
assert_eq!(u8::from(false), 0);
Run

impl From<bool> for u161.28.0[src]

Converts a bool to a u16. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(u16::from(true), 1);
assert_eq!(u16::from(false), 0);
Run

impl From<bool> for u321.28.0[src]

Converts a bool to a u32. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(u32::from(true), 1);
assert_eq!(u32::from(false), 0);
Run

impl From<bool> for u641.28.0[src]

Converts a bool to a u64. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(u64::from(true), 1);
assert_eq!(u64::from(false), 0);
Run

impl From<bool> for u1281.28.0[src]

Converts a bool to a u128. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(u128::from(true), 1);
assert_eq!(u128::from(false), 0);
Run

impl From<bool> for usize1.28.0[src]

Converts a bool to a usize. The resulting value is 0 for false and 1 for true values.

Examples

assert_eq!(usize::from(true), 1);
assert_eq!(usize::from(false), 0);
Run

impl From<bool> for AtomicBool1.24.0[src]

pub fn from(b: bool) -> AtomicBool[src]

Converts a bool into an AtomicBool.

Examples

use std::sync::atomic::AtomicBool;
let atomic_bool = AtomicBool::from(true);
assert_eq!(format!("{:?}", atomic_bool), "true")
Run

impl From<char> for u321.13.0[src]

pub fn from(c: char) -> u32[src]

Converts a char into a u32.

Examples

use std::mem;

let c = 'c';
let u = u32::from(c);
assert!(4 == mem::size_of_val(&u))
Run

impl From<char> for u641.51.0[src]

pub fn from(c: char) -> u64[src]

Converts a char into a u64.

Examples

use std::mem;

let c = '👤';
let u = u64::from(c);
assert!(8 == mem::size_of_val(&u))
Run

impl From<char> for u1281.51.0[src]

pub fn from(c: char) -> u128[src]

Converts a char into a u128.

Examples

use std::mem;

let c = '⚙';
let u = u128::from(c);
assert!(16 == mem::size_of_val(&u))
Run

impl From<char> for String1.46.0[src]

impl From<f32> for f641.6.0[src]

Converts f32 to f64 losslessly.

impl From<i8> for f321.6.0[src]

Converts i8 to f32 losslessly.

impl From<i8> for f641.6.0[src]

Converts i8 to f64 losslessly.

impl From<i8> for i161.5.0[src]

Converts i8 to i16 losslessly.

impl From<i8> for i321.5.0[src]

Converts i8 to i32 losslessly.

impl From<i8> for i641.5.0[src]

Converts i8 to i64 losslessly.

impl From<i8> for i1281.26.0[src]

Converts i8 to i128 losslessly.

impl From<i8> for isize1.5.0[src]

Converts i8 to isize losslessly.

impl From<i8> for AtomicI81.34.0[src]

pub fn from(v: i8) -> AtomicI8[src]

Converts an i8 into an AtomicI8.

impl From<i16> for f321.6.0[src]

Converts i16 to f32 losslessly.

impl From<i16> for f641.6.0[src]

Converts i16 to f64 losslessly.

impl From<i16> for i321.5.0[src]

Converts i16 to i32 losslessly.

impl From<i16> for i641.5.0[src]

Converts i16 to i64 losslessly.

impl From<i16> for i1281.26.0[src]

Converts i16 to i128 losslessly.

impl From<i16> for isize1.26.0[src]

Converts i16 to isize losslessly.

impl From<i16> for AtomicI161.34.0[src]

pub fn from(v: i16) -> AtomicI16[src]

Converts an i16 into an AtomicI16.

impl From<i32> for f641.6.0[src]

Converts i32 to f64 losslessly.

impl From<i32> for i641.5.0[src]

Converts i32 to i64 losslessly.

impl From<i32> for i1281.26.0[src]

Converts i32 to i128 losslessly.

impl From<i32> for AtomicI321.34.0[src]

pub fn from(v: i32) -> AtomicI32[src]

Converts an i32 into an AtomicI32.

impl From<i64> for i1281.26.0[src]

Converts i64 to i128 losslessly.

impl From<i64> for AtomicI641.34.0[src]

pub fn from(v: i64) -> AtomicI64[src]

Converts an i64 into an AtomicI64.

impl From<isize> for AtomicIsize1.23.0[src]

pub fn from(v: isize) -> AtomicIsize[src]

Converts an isize into an AtomicIsize.

impl From<!> for Infallible1.34.0[src]

impl From<!> for TryFromIntError[src]

impl From<u8> for char1.13.0[src]

Maps a byte in 0x00..=0xFF to a char whose code point has the same value, in U+0000..=U+00FF.

Unicode is designed such that this effectively decodes bytes with the character encoding that IANA calls ISO-8859-1. This encoding is compatible with ASCII.

Note that this is different from ISO/IEC 8859-1 a.k.a. ISO 8859-1 (with one less hyphen), which leaves some "blanks", byte values that are not assigned to any character. ISO-8859-1 (the IANA one) assigns them to the C0 and C1 control codes.

Note that this is also different from Windows-1252 a.k.a. code page 1252, which is a superset ISO/IEC 8859-1 that assigns some (not all!) blanks to punctuation and various Latin characters.

To confuse things further, on the Web ascii, iso-8859-1, and windows-1252 are all aliases for a superset of Windows-1252 that fills the remaining blanks with corresponding C0 and C1 control codes.

pub fn from(i: u8) -> char[src]

Converts a u8 into a char.

Examples

use std::mem;

let u = 32 as u8;
let c = char::from(u);
assert!(4 == mem::size_of_val(&c))
Run

impl From<u8> for f321.6.0[src]

Converts u8 to f32 losslessly.

impl From<u8> for f641.6.0[src]

Converts u8 to f64 losslessly.

impl From<u8> for i161.5.0[src]

Converts u8 to i16 losslessly.

impl From<u8> for i321.5.0[src]

Converts u8 to i32 losslessly.

impl From<u8> for i641.5.0[src]

Converts u8 to i64 losslessly.

impl From<u8> for i1281.26.0[src]

Converts u8 to i128 losslessly.

impl From<u8> for isize1.26.0[src]

Converts u8 to isize losslessly.

impl From<u8> for u161.5.0[src]

Converts u8 to u16 losslessly.

impl From<u8> for u321.5.0[src]

Converts u8 to u32 losslessly.

impl From<u8> for u641.5.0[src]

Converts u8 to u64 losslessly.

impl From<u8> for u1281.26.0[src]

Converts u8 to u128 losslessly.

impl From<u8> for usize1.5.0[src]

Converts u8 to usize losslessly.

impl From<u8> for AtomicU81.34.0[src]

pub fn from(v: u8) -> AtomicU8[src]

Converts an u8 into an AtomicU8.

impl From<u16> for f321.6.0[src]

Converts u16 to f32 losslessly.

impl From<u16> for f641.6.0[src]

Converts u16 to f64 losslessly.

impl From<u16> for i321.5.0[src]

Converts u16 to i32 losslessly.

impl From<u16> for i641.5.0[src]

Converts u16 to i64 losslessly.

impl From<u16> for i1281.26.0[src]

Converts u16 to i128 losslessly.

impl From<u16> for u321.5.0[src]

Converts u16 to u32 losslessly.

impl From<u16> for u641.5.0[src]

Converts u16 to u64 losslessly.

impl From<u16> for u1281.26.0[src]

Converts u16 to u128 losslessly.

impl From<u16> for usize1.26.0[src]

Converts u16 to usize losslessly.

impl From<u16> for AtomicU161.34.0[src]

pub fn from(v: u16) -> AtomicU16[src]

Converts an u16 into an AtomicU16.

impl From<u32> for f641.6.0[src]

Converts u32 to f64 losslessly.

impl From<u32> for i641.5.0[src]

Converts u32 to i64 losslessly.

impl From<u32> for i1281.26.0[src]

Converts u32 to i128 losslessly.

impl From<u32> for u641.5.0[src]

Converts u32 to u64 losslessly.

impl From<u32> for u1281.26.0[src]

Converts u32 to u128 losslessly.

impl From<u32> for Ipv4Addr1.1.0[src]

fn from(ip: u32) -> Ipv4Addr[src]

Converts a host byte order u32 into an Ipv4Addr.

Examples

use std::net::Ipv4Addr;

let addr = Ipv4Addr::from(0xcafebabe);
assert_eq!(Ipv4Addr::new(0xca, 0xfe, 0xba, 0xbe), addr);
Run

impl From<u32> for AtomicU321.34.0[src]

pub fn from(v: u32) -> AtomicU32[src]

Converts an u32 into an AtomicU32.

impl From<u64> for i1281.26.0[src]

Converts u64 to i128 losslessly.

impl From<u64> for u1281.26.0[src]

Converts u64 to u128 losslessly.

impl From<u64> for AtomicU641.34.0[src]

pub fn from(v: u64) -> AtomicU64[src]

Converts an u64 into an AtomicU64.

impl From<u128> for Ipv6Addr1.26.0[src]

fn from(ip: u128) -> Ipv6Addr[src]

Convert a host byte order u128 into an Ipv6Addr.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::from(0x102030405060708090A0B0C0D0E0F00D_u128);
assert_eq!(
    Ipv6Addr::new(
        0x1020, 0x3040, 0x5060, 0x7080,
        0x90A0, 0xB0C0, 0xD0E0, 0xF00D,
    ),
    addr);
Run

impl From<usize> for AtomicUsize1.23.0[src]

pub fn from(v: usize) -> AtomicUsize[src]

Converts an usize into an AtomicUsize.

impl From<LayoutError> for TryReserveError[src]

impl From<Box<str, Global>> for String1.18.0[src]

pub fn from(s: Box<str, Global>) -> String[src]

Converts the given boxed str slice to a String. It is notable that the str slice is owned.

Examples

Basic usage:

let s1: String = String::from("hello world");
let s2: Box<str> = s1.into_boxed_str();
let s3: String = String::from(s2);

assert_eq!("hello world", s3)
Run

impl From<Box<CStr, Global>> for CString1.18.0[src]

fn from(s: Box<CStr>) -> CString[src]

Converts a Box<CStr> into a CString without copying or allocating.

impl From<Box<OsStr, Global>> for OsString1.18.0[src]

fn from(boxed: Box<OsStr>) -> OsString[src]

Converts a Box<OsStr> into a OsString without copying or allocating.

impl From<Box<Path, Global>> for PathBuf1.18.0[src]

fn from(boxed: Box<Path>) -> PathBuf[src]

Converts a Box<Path> into a PathBuf

This conversion does not allocate or copy memory.

impl From<CString> for Box<CStr>1.20.0[src]

fn from(s: CString) -> Box<CStr>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a CString into a Box<CStr> without copying or allocating.

impl From<CString> for Rc<CStr>1.24.0[src]

fn from(s: CString) -> Rc<CStr>[src]

Converts a CString into a Rc<CStr> without copying or allocating.

impl From<CString> for Arc<CStr>1.24.0[src]

fn from(s: CString) -> Arc<CStr>[src]

Converts a CString into a Arc<CStr> without copying or allocating.

impl From<CString> for Vec<u8>1.7.0[src]

fn from(s: CString) -> Vec<u8>

Notable traits for Vec<u8>

impl Write for Vec<u8>
[src]

Converts a CString into a Vec<u8>.

The conversion consumes the CString, and removes the terminating NUL byte.

impl From<NulError> for Error[src]

fn from(_: NulError) -> Error[src]

Converts a NulError into a io::Error.

impl From<OsString> for Box<OsStr>1.20.0[src]

fn from(s: OsString) -> Box<OsStr>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a OsString into a Box<OsStr> without copying or allocating.

impl From<OsString> for PathBuf[src]

fn from(s: OsString) -> PathBuf[src]

Converts a OsString into a PathBuf

This conversion does not allocate or copy memory.

impl From<OsString> for Rc<OsStr>1.24.0[src]

fn from(s: OsString) -> Rc<OsStr>[src]

Converts a OsString into a Rc<OsStr> without copying or allocating.

impl From<OsString> for Arc<OsStr>1.24.0[src]

fn from(s: OsString) -> Arc<OsStr>[src]

Converts a OsString into a Arc<OsStr> without copying or allocating.

impl From<File> for Stdio1.20.0[src]

fn from(file: File) -> Stdio[src]

Converts a File into a Stdio

Examples

File will be converted to Stdio using Stdio::from under the hood.

use std::fs::File;
use std::process::Command;

// With the `foo.txt` file containing `Hello, world!"
let file = File::open("foo.txt").unwrap();

let reverse = Command::new("rev")
    .stdin(file)  // Implicit File conversion into a Stdio
    .output()
    .expect("failed reverse command");

assert_eq!(reverse.stdout, b"!dlrow ,olleH");
Run

impl From<Ipv4Addr> for IpAddr1.16.0[src]

fn from(ipv4: Ipv4Addr) -> IpAddr[src]

Copies this address to a new IpAddr::V4.

Examples

use std::net::{IpAddr, Ipv4Addr};

let addr = Ipv4Addr::new(127, 0, 0, 1);

assert_eq!(
    IpAddr::V4(addr),
    IpAddr::from(addr)
)
Run

impl From<Ipv4Addr> for u321.1.0[src]

fn from(ip: Ipv4Addr) -> u32[src]

Converts an Ipv4Addr into a host byte order u32.

Examples

use std::net::Ipv4Addr;

let addr = Ipv4Addr::new(0xca, 0xfe, 0xba, 0xbe);
assert_eq!(0xcafebabe, u32::from(addr));
Run

impl From<Ipv6Addr> for IpAddr1.16.0[src]

fn from(ipv6: Ipv6Addr) -> IpAddr[src]

Copies this address to a new IpAddr::V6.

Examples

use std::net::{IpAddr, Ipv6Addr};

let addr = Ipv6Addr::new(0, 0, 0, 0, 0, 0xffff, 0xc00a, 0x2ff);

assert_eq!(
    IpAddr::V6(addr),
    IpAddr::from(addr)
);
Run

impl From<Ipv6Addr> for u1281.26.0[src]

fn from(ip: Ipv6Addr) -> u128[src]

Convert an Ipv6Addr into a host byte order u128.

Examples

use std::net::Ipv6Addr;

let addr = Ipv6Addr::new(
    0x1020, 0x3040, 0x5060, 0x7080,
    0x90A0, 0xB0C0, 0xD0E0, 0xF00D,
);
assert_eq!(0x102030405060708090A0B0C0D0E0F00D_u128, u128::from(addr));
Run

impl From<SocketAddrV4> for SocketAddr1.16.0[src]

impl From<SocketAddrV6> for SocketAddr1.16.0[src]

impl From<NonZeroI8> for i81.31.0[src]

pub fn from(nonzero: NonZeroI8) -> i8[src]

Converts a NonZeroI8 into an i8

impl From<NonZeroI8> for NonZeroI161.41.0[src]

Converts NonZeroI8 to NonZeroI16 losslessly.

impl From<NonZeroI8> for NonZeroI321.41.0[src]

Converts NonZeroI8 to NonZeroI32 losslessly.

impl From<NonZeroI8> for NonZeroI641.41.0[src]

Converts NonZeroI8 to NonZeroI64 losslessly.

impl From<NonZeroI8> for NonZeroI1281.41.0[src]

Converts NonZeroI8 to NonZeroI128 losslessly.

impl From<NonZeroI8> for NonZeroIsize1.41.0[src]

Converts NonZeroI8 to NonZeroIsize losslessly.

impl From<NonZeroI16> for i161.31.0[src]

pub fn from(nonzero: NonZeroI16) -> i16[src]

Converts a NonZeroI16 into an i16

impl From<NonZeroI16> for NonZeroI321.41.0[src]

Converts NonZeroI16 to NonZeroI32 losslessly.

impl From<NonZeroI16> for NonZeroI641.41.0[src]

Converts NonZeroI16 to NonZeroI64 losslessly.

impl From<NonZeroI16> for NonZeroI1281.41.0[src]

Converts NonZeroI16 to NonZeroI128 losslessly.

impl From<NonZeroI16> for NonZeroIsize1.41.0[src]

Converts NonZeroI16 to NonZeroIsize losslessly.

impl From<NonZeroI32> for i321.31.0[src]

pub fn from(nonzero: NonZeroI32) -> i32[src]

Converts a NonZeroI32 into an i32

impl From<NonZeroI32> for NonZeroI641.41.0[src]

Converts NonZeroI32 to NonZeroI64 losslessly.

impl From<NonZeroI32> for NonZeroI1281.41.0[src]

Converts NonZeroI32 to NonZeroI128 losslessly.

impl From<NonZeroI64> for i641.31.0[src]

pub fn from(nonzero: NonZeroI64) -> i64[src]

Converts a NonZeroI64 into an i64

impl From<NonZeroI64> for NonZeroI1281.41.0[src]

Converts NonZeroI64 to NonZeroI128 losslessly.

impl From<NonZeroI128> for i1281.31.0[src]

pub fn from(nonzero: NonZeroI128) -> i128[src]

Converts a NonZeroI128 into an i128

impl From<NonZeroIsize> for isize1.31.0[src]

pub fn from(nonzero: NonZeroIsize) -> isize[src]

Converts a NonZeroIsize into an isize

impl From<NonZeroU8> for u81.31.0[src]

pub fn from(nonzero: NonZeroU8) -> u8[src]

Converts a NonZeroU8 into an u8

impl From<NonZeroU8> for NonZeroI161.41.0[src]

Converts NonZeroU8 to NonZeroI16 losslessly.

impl From<NonZeroU8> for NonZeroI321.41.0[src]

Converts NonZeroU8 to NonZeroI32 losslessly.

impl From<NonZeroU8> for NonZeroI641.41.0[src]

Converts NonZeroU8 to NonZeroI64 losslessly.

impl From<NonZeroU8> for NonZeroI1281.41.0[src]

Converts NonZeroU8 to NonZeroI128 losslessly.

impl From<NonZeroU8> for NonZeroIsize1.41.0[src]

Converts NonZeroU8 to NonZeroIsize losslessly.

impl From<NonZeroU8> for NonZeroU161.41.0[src]

Converts NonZeroU8 to NonZeroU16 losslessly.

impl From<NonZeroU8> for NonZeroU321.41.0[src]

Converts NonZeroU8 to NonZeroU32 losslessly.

impl From<NonZeroU8> for NonZeroU641.41.0[src]

Converts NonZeroU8 to NonZeroU64 losslessly.

impl From<NonZeroU8> for NonZeroU1281.41.0[src]

Converts NonZeroU8 to NonZeroU128 losslessly.

impl From<NonZeroU8> for NonZeroUsize1.41.0[src]

Converts NonZeroU8 to NonZeroUsize losslessly.

impl From<NonZeroU16> for u161.31.0[src]

pub fn from(nonzero: NonZeroU16) -> u16[src]

Converts a NonZeroU16 into an u16

impl From<NonZeroU16> for NonZeroI321.41.0[src]

Converts NonZeroU16 to NonZeroI32 losslessly.

impl From<NonZeroU16> for NonZeroI641.41.0[src]

Converts NonZeroU16 to NonZeroI64 losslessly.

impl From<NonZeroU16> for NonZeroI1281.41.0[src]

Converts NonZeroU16 to NonZeroI128 losslessly.

impl From<NonZeroU16> for NonZeroU321.41.0[src]

Converts NonZeroU16 to NonZeroU32 losslessly.

impl From<NonZeroU16> for NonZeroU641.41.0[src]

Converts NonZeroU16 to NonZeroU64 losslessly.

impl From<NonZeroU16> for NonZeroU1281.41.0[src]

Converts NonZeroU16 to NonZeroU128 losslessly.

impl From<NonZeroU16> for NonZeroUsize1.41.0[src]

Converts NonZeroU16 to NonZeroUsize losslessly.

impl From<NonZeroU32> for u321.31.0[src]

pub fn from(nonzero: NonZeroU32) -> u32[src]

Converts a NonZeroU32 into an u32

impl From<NonZeroU32> for NonZeroI641.41.0[src]

Converts NonZeroU32 to NonZeroI64 losslessly.

impl From<NonZeroU32> for NonZeroI1281.41.0[src]

Converts NonZeroU32 to NonZeroI128 losslessly.

impl From<NonZeroU32> for NonZeroU641.41.0[src]

Converts NonZeroU32 to NonZeroU64 losslessly.

impl From<NonZeroU32> for NonZeroU1281.41.0[src]

Converts NonZeroU32 to NonZeroU128 losslessly.

impl From<NonZeroU64> for u641.31.0[src]

pub fn from(nonzero: NonZeroU64) -> u64[src]

Converts a NonZeroU64 into an u64

impl From<NonZeroU64> for NonZeroI1281.41.0[src]

Converts NonZeroU64 to NonZeroI128 losslessly.

impl From<NonZeroU64> for NonZeroU1281.41.0[src]

Converts NonZeroU64 to NonZeroU128 losslessly.

impl From<NonZeroU128> for u1281.31.0[src]

pub fn from(nonzero: NonZeroU128) -> u128[src]

Converts a NonZeroU128 into an u128

impl From<NonZeroUsize> for usize1.31.0[src]

pub fn from(nonzero: NonZeroUsize) -> usize[src]

Converts a NonZeroUsize into an usize

impl From<PathBuf> for Box<Path>1.20.0[src]

fn from(p: PathBuf) -> Box<Path>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a PathBuf into a Box<Path>

This conversion currently should not allocate memory, but this behavior is not guaranteed on all platforms or in all future versions.

impl From<PathBuf> for OsString1.14.0[src]

fn from(path_buf: PathBuf) -> OsString[src]

Converts a PathBuf into a OsString

This conversion does not allocate or copy memory.

impl From<PathBuf> for Rc<Path>1.24.0[src]

fn from(s: PathBuf) -> Rc<Path>[src]

Converts a PathBuf into an Rc by moving the PathBuf data into a new Rc buffer.

impl From<PathBuf> for Arc<Path>1.24.0[src]

fn from(s: PathBuf) -> Arc<Path>[src]

Converts a PathBuf into an Arc by moving the PathBuf data into a new Arc buffer.

impl From<ChildStderr> for Stdio1.20.0[src]

fn from(child: ChildStderr) -> Stdio[src]

Converts a ChildStderr into a Stdio

Examples

use std::process::{Command, Stdio};

let reverse = Command::new("rev")
    .arg("non_existing_file.txt")
    .stderr(Stdio::piped())
    .spawn()
    .expect("failed reverse command");

let cat = Command::new("cat")
    .arg("-")
    .stdin(reverse.stderr.unwrap()) // Converted into a Stdio here
    .output()
    .expect("failed echo command");

assert_eq!(
    String::from_utf8_lossy(&cat.stdout),
    "rev: cannot open non_existing_file.txt: No such file or directory\n"
);
Run

impl From<ChildStdin> for Stdio1.20.0[src]

fn from(child: ChildStdin) -> Stdio[src]

Converts a ChildStdin into a Stdio

Examples

ChildStdin will be converted to Stdio using Stdio::from under the hood.

use std::process::{Command, Stdio};

let reverse = Command::new("rev")
    .stdin(Stdio::piped())
    .spawn()
    .expect("failed reverse command");

let _echo = Command::new("echo")
    .arg("Hello, world!")
    .stdout(reverse.stdin.unwrap()) // Converted into a Stdio here
    .output()
    .expect("failed echo command");

// "!dlrow ,olleH" echoed to console
Run

impl From<ChildStdout> for Stdio1.20.0[src]

fn from(child: ChildStdout) -> Stdio[src]

Converts a ChildStdout into a Stdio

Examples

ChildStdout will be converted to Stdio using Stdio::from under the hood.

use std::process::{Command, Stdio};

let hello = Command::new("echo")
    .arg("Hello, world!")
    .stdout(Stdio::piped())
    .spawn()
    .expect("failed echo command");

let reverse = Command::new("rev")
    .stdin(hello.stdout.unwrap())  // Converted into a Stdio here
    .output()
    .expect("failed reverse command");

assert_eq!(reverse.stdout, b"!dlrow ,olleH\n");
Run

impl From<String> for Box<str, Global>1.20.0[src]

pub fn from(s: String) -> Box<str, Global>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts the given String to a boxed str slice that is owned.

Examples

Basic usage:

let s1: String = String::from("hello world");
let s2: Box<str> = Box::from(s1);
let s3: String = String::from(s2);

assert_eq!("hello world", s3)
Run

impl From<String> for Box<dyn Error + Send + Sync>[src]

fn from(err: String) -> Box<dyn Error + Send + Sync>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a String into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;
use std::mem;

let a_string_error = "a string error".to_string();
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_string_error);
assert!(
    mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))
Run

impl From<String> for Box<dyn Error>1.6.0[src]

fn from(str_err: String) -> Box<dyn Error>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a String into a box of dyn Error.

Examples

use std::error::Error;
use std::mem;

let a_string_error = "a string error".to_string();
let a_boxed_error = Box::<dyn Error>::from(a_string_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))
Run

impl From<String> for OsString[src]

fn from(s: String) -> OsString[src]

Converts a String into a OsString.

The conversion copies the data, and includes an allocation on the heap.

impl From<String> for PathBuf[src]

fn from(s: String) -> PathBuf[src]

Converts a String into a PathBuf

This conversion does not allocate or copy memory.

impl From<String> for Rc<str>1.21.0[src]

impl From<String> for Arc<str>1.21.0[src]

impl From<String> for Vec<u8, Global>1.14.0[src]

pub fn from(string: String) -> Vec<u8, Global>

Notable traits for Vec<u8>

impl Write for Vec<u8>
[src]

Converts the given String to a vector Vec that holds values of type u8.

Examples

Basic usage:

let s1 = String::from("hello world");
let v1 = Vec::from(s1);

for b in v1 {
    println!("{}", b);
}
Run

impl From<RecvError> for RecvTimeoutError1.24.0[src]

fn from(err: RecvError) -> RecvTimeoutError[src]

Converts a RecvError into a RecvTimeoutError.

This conversion always returns RecvTimeoutError::Disconnected.

No data is allocated on the heap.

impl From<RecvError> for TryRecvError1.24.0[src]

fn from(err: RecvError) -> TryRecvError[src]

Converts a RecvError into a TryRecvError.

This conversion always returns TryRecvError::Disconnected.

No data is allocated on the heap.

impl From<Vec<NonZeroU8, Global>> for CString1.43.0[src]

fn from(v: Vec<NonZeroU8>) -> CString[src]

Converts a Vec<NonZeroU8> into a CString without copying nor checking for inner null bytes.

impl From<StreamResult> for Result<MZStatus, MZError>

impl<'_> From<&'_ str> for Box<str, Global>1.17.0[src]

pub fn from(s: &str) -> Box<str, Global>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a &str into a Box<str>

This conversion allocates on the heap and performs a copy of s.

Examples

let boxed: Box<str> = Box::from("hello");
println!("{}", boxed);
Run

impl<'_> From<&'_ str> for Rc<str>1.21.0[src]

impl<'_> From<&'_ str> for String[src]

impl<'_> From<&'_ str> for Arc<str>1.21.0[src]

impl<'_> From<&'_ str> for Vec<u8, Global>[src]

impl<'_> From<&'_ String> for String1.35.0[src]

impl<'_> From<&'_ StreamResult> for Result<MZStatus, MZError>

impl<'_> From<&'_ mut str> for String1.44.0[src]

pub fn from(s: &mut str) -> String[src]

Converts a &mut str into a String.

The result is allocated on the heap.

impl<'_> From<Cow<'_, str>> for Box<str, Global>1.45.0[src]

impl<'_, T> From<Cow<'_, [T]>> for Box<[T], Global> where
    T: Copy
1.45.0[src]

impl<'_, T> From<&'_ T> for NonNull<T> where
    T: ?Sized
1.25.0[src]

impl<'_, T> From<&'_ mut T> for NonNull<T> where
    T: ?Sized
1.25.0[src]

impl<'_, T> From<&'_ [T]> for Box<[T], Global> where
    T: Copy
1.17.0[src]

pub fn from(slice: &[T]) -> Box<[T], Global>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a &[T] into a Box<[T]>

This conversion allocates on the heap and performs a copy of slice.

Examples

// create a &[u8] which will be used to create a Box<[u8]>
let slice: &[u8] = &[104, 101, 108, 108, 111];
let boxed_slice: Box<[u8]> = Box::from(slice);

println!("{:?}", boxed_slice);
Run

impl<'_, T> From<&'_ [T]> for Rc<[T]> where
    T: Clone
1.21.0[src]

impl<'_, T> From<&'_ [T]> for Arc<[T]> where
    T: Clone
1.21.0[src]

impl<'_, T> From<&'_ [T]> for Vec<T, Global> where
    T: Clone
[src]

impl<'_, T> From<&'_ mut [T]> for Vec<T, Global> where
    T: Clone
1.19.0[src]

impl<'a> From<&'_ str> for Box<dyn Error + Send + Sync + 'a>[src]

fn from(err: &str) -> Box<dyn Error + Send + Sync + 'a>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a str into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;
use std::mem;

let a_str_error = "a str error";
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_str_error);
assert!(
    mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))
Run

impl<'a> From<&'a str> for Cow<'a, str>[src]

impl<'a> From<&'a CStr> for Cow<'a, CStr>1.28.0[src]

impl<'a> From<&'a CString> for Cow<'a, CStr>1.28.0[src]

impl<'a> From<&'a OsStr> for Cow<'a, OsStr>1.28.0[src]

impl<'a> From<&'a OsString> for Cow<'a, OsStr>1.28.0[src]

impl<'a> From<&'a Path> for Cow<'a, Path>1.6.0[src]

impl<'a> From<&'a PathBuf> for Cow<'a, Path>1.28.0[src]

impl<'a> From<&'a String> for Cow<'a, str>1.28.0[src]

impl<'a> From<Cow<'a, str>> for Box<dyn Error>1.22.0[src]

fn from(err: Cow<'a, str>) -> Box<dyn Error>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a Cow into a box of dyn Error.

Examples

use std::error::Error;
use std::mem;
use std::borrow::Cow;

let a_cow_str_error = Cow::from("a str error");
let a_boxed_error = Box::<dyn Error>::from(a_cow_str_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))
Run

impl<'a> From<Cow<'a, str>> for String1.14.0[src]

impl<'a> From<Cow<'a, CStr>> for CString1.28.0[src]

impl<'a> From<Cow<'a, OsStr>> for OsString1.28.0[src]

impl<'a> From<Cow<'a, Path>> for PathBuf1.28.0[src]

impl<'a> From<CString> for Cow<'a, CStr>1.28.0[src]

impl<'a> From<OsString> for Cow<'a, OsStr>1.28.0[src]

impl<'a> From<PathBuf> for Cow<'a, Path>1.6.0[src]

impl<'a> From<String> for Cow<'a, str>[src]

impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Send + Sync + 'a>1.22.0[src]

fn from(err: Cow<'b, str>) -> Box<dyn Error + Send + Sync + 'a>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a Cow into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;
use std::mem;
use std::borrow::Cow;

let a_cow_str_error = Cow::from("a str error");
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_cow_str_error);
assert!(
    mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))
Run

impl<'a, B> From<Cow<'a, B>> for Rc<B> where
    B: ToOwned + ?Sized,
    Rc<B>: From<&'a B>,
    Rc<B>: From<<B as ToOwned>::Owned>, 
1.45.0[src]

impl<'a, B> From<Cow<'a, B>> for Arc<B> where
    B: ToOwned + ?Sized,
    Arc<B>: From<&'a B>,
    Arc<B>: From<<B as ToOwned>::Owned>, 
1.45.0[src]

impl<'a, E: Error + 'a> From<E> for Box<dyn Error + 'a>[src]

fn from(err: E) -> Box<dyn Error + 'a>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a type of Error into a box of dyn Error.

Examples

use std::error::Error;
use std::fmt;
use std::mem;

#[derive(Debug)]
struct AnError;

impl fmt::Display for AnError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f , "An error")
    }
}

impl Error for AnError {}

let an_error = AnError;
assert!(0 == mem::size_of_val(&an_error));
let a_boxed_error = Box::<dyn Error>::from(an_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))
Run

impl<'a, E: Error + Send + Sync + 'a> From<E> for Box<dyn Error + Send + Sync + 'a>[src]

fn from(err: E) -> Box<dyn Error + Send + Sync + 'a>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a type of Error + Send + Sync into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;
use std::fmt;
use std::mem;

#[derive(Debug)]
struct AnError;

impl fmt::Display for AnError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f , "An error")
    }
}

impl Error for AnError {}

unsafe impl Send for AnError {}

unsafe impl Sync for AnError {}

let an_error = AnError;
assert!(0 == mem::size_of_val(&an_error));
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(an_error);
assert!(
    mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))
Run

impl<'a, T> From<&'a Option<T>> for Option<&'a T>1.30.0[src]

pub fn from(o: &'a Option<T>) -> Option<&'a T>[src]

Converts from &Option<T> to Option<&T>.

Examples

Converts an Option<String> into an Option<usize>, preserving the original. The map method takes the self argument by value, consuming the original, so this technique uses as_ref to first take an Option to a reference to the value inside the original.

let s: Option<String> = Some(String::from("Hello, Rustaceans!"));
let o: Option<usize> = Option::from(&s).map(|ss: &String| ss.len());

println!("Can still print s: {:?}", s);

assert_eq!(o, Some(18));
Run

impl<'a, T> From<&'a Vec<T, Global>> for Cow<'a, [T]> where
    T: Clone
1.28.0[src]

impl<'a, T> From<&'a mut Option<T>> for Option<&'a mut T>1.30.0[src]

pub fn from(o: &'a mut Option<T>) -> Option<&'a mut T>[src]

Converts from &mut Option<T> to Option<&mut T>

Examples

let mut s = Some(String::from("Hello"));
let o: Option<&mut String> = Option::from(&mut s);

match o {
    Some(t) => *t = String::from("Hello, Rustaceans!"),
    None => (),
}

assert_eq!(s, Some(String::from("Hello, Rustaceans!")));
Run

impl<'a, T> From<Cow<'a, [T]>> for Vec<T, Global> where
    [T]: ToOwned,
    <[T] as ToOwned>::Owned == Vec<T, Global>, 
1.14.0[src]

impl<'a, T> From<&'a [T]> for Cow<'a, [T]> where
    T: Clone
1.8.0[src]

impl<'a, T> From<Vec<T, Global>> for Cow<'a, [T]> where
    T: Clone
1.8.0[src]

impl<A> From<Box<str, A>> for Box<[u8], A> where
    A: Allocator
1.19.0[src]

pub fn from(s: Box<str, A>) -> Box<[u8], A>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a Box<str> into a Box<[u8]>

This conversion does not allocate on the heap and happens in place.

Examples

// create a Box<str> which will be used to create a Box<[u8]>
let boxed: Box<str> = Box::from("hello");
let boxed_str: Box<[u8]> = Box::from(boxed);

// create a &[u8] which will be used to create a Box<[u8]>
let slice: &[u8] = &[104, 101, 108, 108, 111];
let boxed_slice = Box::from(slice);

assert_eq!(boxed_slice, boxed_str);
Run

impl<I: Into<IpAddr>> From<(I, u16)> for SocketAddr1.17.0[src]

fn from(pieces: (I, u16)) -> SocketAddr[src]

Converts a tuple struct (Into<IpAddr>, u16) into a SocketAddr.

This conversion creates a SocketAddr::V4 for a IpAddr::V4 and creates a SocketAddr::V6 for a IpAddr::V6.

u16 is treated as port of the newly created SocketAddr.

impl<T> From<!> for T1.34.0[src]

Stability note: This impl does not yet exist, but we are "reserving space" to add it in the future. See rust-lang/rust#64715 for details.

impl<T> From<*mut T> for AtomicPtr<T>1.23.0[src]

impl<T> From<Box<T, Global>> for Rc<T> where
    T: ?Sized
1.21.0[src]

impl<T> From<Box<T, Global>> for Arc<T> where
    T: ?Sized
1.21.0[src]

impl<T> From<BinaryHeap<T>> for Vec<T, Global>1.5.0[src]

pub fn from(heap: BinaryHeap<T>) -> Vec<T, Global>

Notable traits for Vec<u8>

impl Write for Vec<u8>
[src]

Converts a BinaryHeap<T> into a Vec<T>.

This conversion requires no data movement or allocation, and has constant time complexity.

impl<T> From<VecDeque<T>> for Vec<T, Global>1.10.0[src]

pub fn from(other: VecDeque<T>) -> Vec<T, Global>

Notable traits for Vec<u8>

impl Write for Vec<u8>
[src]

Turn a VecDeque<T> into a Vec<T>.

This never needs to re-allocate, but does need to do O(n) data movement if the circular buffer doesn't happen to be at the beginning of the allocation.

Examples

use std::collections::VecDeque;

// This one is *O*(1).
let deque: VecDeque<_> = (1..5).collect();
let ptr = deque.as_slices().0.as_ptr();
let vec = Vec::from(deque);
assert_eq!(vec, [1, 2, 3, 4]);
assert_eq!(vec.as_ptr(), ptr);

// This one needs data rearranging.
let mut deque: VecDeque<_> = (1..5).collect();
deque.push_front(9);
deque.push_front(8);
let ptr = deque.as_slices().1.as_ptr();
let vec = Vec::from(deque);
assert_eq!(vec, [8, 9, 1, 2, 3, 4]);
assert_eq!(vec.as_ptr(), ptr);
Run

impl<T> From<SendError<T>> for TrySendError<T>1.24.0[src]

fn from(err: SendError<T>) -> TrySendError<T>[src]

Converts a SendError<T> into a TrySendError<T>.

This conversion always returns a TrySendError::Disconnected containing the data in the SendError<T>.

No data is allocated on the heap.

impl<T> From<PoisonError<T>> for TryLockError<T>[src]

impl<T> From<Vec<T, Global>> for BinaryHeap<T> where
    T: Ord
1.5.0[src]

pub fn from(vec: Vec<T, Global>) -> BinaryHeap<T>[src]

Converts a Vec<T> into a BinaryHeap<T>.

This conversion happens in-place, and has O(n) time complexity.

impl<T> From<Vec<T, Global>> for VecDeque<T>1.10.0[src]

pub fn from(other: Vec<T, Global>) -> VecDeque<T>[src]

Turn a Vec<T> into a VecDeque<T>.

This avoids reallocating where possible, but the conditions for that are strict, and subject to change, and so shouldn't be relied upon unless the Vec<T> came from From<VecDeque<T>> and hasn't been reallocated.

impl<T> From<Vec<T, Global>> for Rc<[T]>1.21.0[src]

impl<T> From<Vec<T, Global>> for Arc<[T]>1.21.0[src]

impl<T> From<T> for Option<T>1.12.0[src]

pub fn from(val: T) -> Option<T>[src]

Copies val into a new Some.

Examples

let o: Option<u8> = Option::from(67);

assert_eq!(Some(67), o);
Run

impl<T> From<T> for Poll<T>1.36.0[src]

pub fn from(t: T) -> Poll<T>[src]

Convert to a Ready variant.

Example

assert_eq!(Poll::from(true), Poll::Ready(true));
Run

impl<T> From<T> for Box<T, Global>1.6.0[src]

pub fn from(t: T) -> Box<T, Global>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a generic type T into a Box<T>

The conversion allocates on the heap and moves t from the stack into it.

Examples

let x = 5;
let boxed = Box::new(5);

assert_eq!(Box::from(x), boxed);
Run

impl<T> From<T> for Cell<T>1.12.0[src]

impl<T> From<T> for RefCell<T>1.12.0[src]

impl<T> From<T> for UnsafeCell<T>1.12.0[src]

impl<T> From<T> for OnceCell<T>[src]

impl<T> From<T> for SyncOnceCell<T>[src]

impl<T> From<T> for Rc<T>1.6.0[src]

impl<T> From<T> for Arc<T>1.6.0[src]

impl<T> From<T> for Mutex<T>1.24.0[src]

fn from(t: T) -> Self[src]

Creates a new mutex in an unlocked state ready for use. This is equivalent to Mutex::new.

impl<T> From<T> for RwLock<T>1.24.0[src]

fn from(t: T) -> Self[src]

Creates a new instance of an RwLock<T> which is unlocked. This is equivalent to RwLock::new.

impl<T> From<T> for T[src]

impl<T> From<Unique<T>> for NonNull<T> where
    T: ?Sized
[src]

impl<T, A> From<Box<[T], A>> for Vec<T, A> where
    A: Allocator
1.18.0[src]

impl<T, A> From<Box<T, A>> for Pin<Box<T, A>> where
    T: ?Sized,
    A: Allocator + 'static, 
1.33.0[src]

pub fn from(boxed: Box<T, A>) -> Pin<Box<T, A>>

Notable traits for Pin<P>

impl<P> Future for Pin<P> where
    P: Unpin + DerefMut,
    <P as Deref>::Target: Future
type Output = <<P as Deref>::Target as Future>::Output;
[src]

Converts a Box<T> into a Pin<Box<T>>

This conversion does not allocate on the heap and happens in place.

impl<T, A> From<Vec<T, A>> for Box<[T], A> where
    A: Allocator
1.20.0[src]

impl<T, const N: usize> From<[T; N]> for Box<[T], Global>1.45.0[src]

pub fn from(array: [T; N]) -> Box<[T], Global>

Notable traits for Box<F, A>

impl<F, A> Future for Box<F, A> where
    F: Unpin + Future + ?Sized,
    A: Allocator + 'static, 
type Output = <F as Future>::Output;impl<I, A> Iterator for Box<I, A> where
    I: Iterator + ?Sized,
    A: Allocator
type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for Box<R>impl<W: Write + ?Sized> Write for Box<W>
[src]

Converts a [T; N] into a Box<[T]>

This conversion moves the array to newly heap-allocated memory.

Examples

let boxed: Box<[u8]> = Box::from([4, 2]);
println!("{:?}", boxed);
Run

impl<T, const N: usize> From<[T; N]> for Vec<T, Global>1.44.0[src]

impl<T: ?Sized + AsRef<OsStr>> From<&'_ T> for OsString[src]

impl<T: ?Sized + AsRef<OsStr>> From<&'_ T> for PathBuf[src]

impl<W> From<IntoInnerError<W>> for Error[src]

impl<W> From<Arc<W>> for RawWaker where
    W: 'static + Wake + Send + Sync
1.51.0[src]

impl<W> From<Arc<W>> for Waker where
    W: 'static + Wake + Send + Sync
1.51.0[src]

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