Trait dorset::core::vari::From

pub trait From<T> {
    fn from(T) -> Self;
}

Simple and safe type conversions in to Self. It is the reciprocal of Into.

This trait is useful when performing error handling as described by the book and is closely related to the ? operator.

When constructing a function that is capable of failing the return type will generally be of the form Result<T, E>.

The From trait allows for simplification of error handling by providing a means of returning a single error type that encapsulates numerous possible erroneous situations.

This trait is not limited to error handling, rather the general case for this trait would be in any type conversions to have an explicit definition of how they are performed.

Note: this trait must not fail. If the conversion can fail, use TryFrom or a dedicated method which returns an Option<T> or a Result<T, E>.

Generic Implementations

• From<T> for U implies Into<U>for T
• from is reflexive, which means that From<T> for T is implemented

Examples

String implements From<&str>:

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

assert_eq!(string, other_string);

An example usage for error handling:

use std::io::{self, Read};
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 file = std::fs::File::open("test")?;
    let mut contents = String::new();
    file.read_to_string(&mut contents)?;
    let num: i32 = contents.trim().parse()?;
    Ok(num)
}

Required Methods

fn from(T) -> Self

Performs the conversion.

Implementations on Foreign Types

impl From<NulError> for Error

fn from(NulError) -> Error

impl From<File> for Stdio

fn from(file: File) -> Stdio

impl From<[u16; 8]> for IpAddr

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

impl From<String> for Box<Error + 'static + Send + Sync>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl From<OsString> for PathBuf

fn from(s: OsString) -> PathBuf

impl From<Box<CStr>> for CString

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

impl<'a, E> From<E> for Box<Error + 'a> where
    E: 'a + Error, 

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl From<CString> for Vec<u8>

Important traits for Vec<u8>

impl Write for Vec<u8>

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

impl<W> From<IntoInnerError<W>> for Error

fn from(iie: IntoInnerError<W>) -> Error

impl<'a> From<&'a Path> for Cow<'a, Path>

fn from(s: &'a Path) -> Cow<'a, Path>

impl<'a> From<Cow<'a, str>> for Box<Error + 'static>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl From<PathBuf> for OsString

fn from(path_buf: PathBuf) -> OsString

impl From<PathBuf> for Arc<Path>

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

impl<'a> From<&'a OsStr> for Box<OsStr>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

fn from(s: &'a OsStr) -> Box<OsStr>

impl From<[u8; 16]> for Ipv6Addr

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

impl From<[u8; 16]> for IpAddr

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

impl From<[u8; 4]> for IpAddr

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

impl<T> From<SendError<T>> for TrySendError<T>

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

impl From<DefaultEnvKey> for OsString

fn from(k: DefaultEnvKey) -> OsString

impl<'a, T> From<&'a T> for PathBuf where
    T: AsRef<OsStr> + ?Sized, 

fn from(s: &'a T) -> PathBuf

impl From<Ipv4Addr> for IpAddr

fn from(ipv4: Ipv4Addr) -> IpAddr

impl From<Ipv6Addr> for IpAddr

fn from(ipv6: Ipv6Addr) -> IpAddr

impl<T> From<T> for Mutex<T>

fn from(t: T) -> Mutex<T>

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

impl<'a> From<PathBuf> for Cow<'a, Path>

fn from(s: PathBuf) -> Cow<'a, Path>

impl From<u128> for Ipv6Addr

fn from(ip: u128) -> Ipv6Addr

impl From<String> for PathBuf

fn from(s: String) -> PathBuf

impl From<RecvError> for TryRecvError

fn from(err: RecvError) -> TryRecvError

impl From<OsString> for Arc<OsStr>

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

impl From<Ipv6Addr> for u128

fn from(ip: Ipv6Addr) -> u128

impl From<CString> for Box<CStr>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl From<ChildStderr> for Stdio

fn from(child: ChildStderr) -> Stdio

impl<'a, 'b> From<&'b str> for Box<Error + 'a + Send + Sync>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl<'a> From<&'a OsStr> for Arc<OsStr>

fn from(s: &OsStr) -> Arc<OsStr>

impl From<ErrorKind> for Error

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

impl From<ChildStdin> for Stdio

fn from(child: ChildStdin) -> Stdio

impl<'a, E> From<E> for Box<Error + 'a + Send + Sync> where
    E: 'a + Error + Send + Sync, 

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl From<u32> for Ipv4Addr

fn from(ip: u32) -> Ipv4Addr

It performs the conversion in network order (big-endian).

impl From<CString> for Arc<CStr>

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

impl<T> From<T> for RwLock<T>

fn from(t: T) -> RwLock<T>

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

impl From<String> for Box<Error + 'static>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

fn from(str_err: String) -> Box<Error + 'static>

impl From<[u16; 8]> for Ipv6Addr

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

impl<'a, T> From<&'a T> for OsString where
    T: AsRef<OsStr> + ?Sized, 

fn from(s: &'a T) -> OsString

impl From<[u8; 4]> for Ipv4Addr

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

impl<'a> From<&'a CStr> for CString

fn from(s: &'a CStr) -> CString

impl<'a> From<&'a str> for Box<Error + 'static>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl From<String> for OsString

fn from(s: String) -> OsString

impl From<SocketAddrV6> for SocketAddr

fn from(sock6: SocketAddrV6) -> SocketAddr

impl<T> From<PoisonError<T>> for TryLockError<T>

fn from(err: PoisonError<T>) -> TryLockError<T>

impl From<Box<Path>> for PathBuf

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

impl From<OsString> for Box<OsStr>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl From<RecvError> for RecvTimeoutError

fn from(err: RecvError) -> RecvTimeoutError

impl<'a> From<&'a Path> for Arc<Path>

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

impl<'a, 'b> From<Cow<'b, str>> for Box<Error + 'a + Send + Sync>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl From<Ipv4Addr> for u32

fn from(ip: Ipv4Addr) -> u32

It performs the conversion in network order (big-endian).

impl From<PathBuf> for Box<Path>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl<'a> From<&'a Path> for Box<Path>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

fn from(path: &'a Path) -> Box<Path>

impl<'a> From<&'a CStr> for Arc<CStr>

fn from(s: &CStr) -> Arc<CStr>

impl<I> From<(I, u16)> for SocketAddr where
    I: Into<IpAddr>, 

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

impl From<Box<OsStr>> for OsString

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

impl From<SocketAddrV4> for SocketAddr

fn from(sock4: SocketAddrV4) -> SocketAddr

impl From<ChildStdout> for Stdio

fn from(child: ChildStdout) -> Stdio

impl<'a> From<&'a CStr> for Box<CStr>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

fn from(s: &'a CStr) -> Box<CStr>

impl From<i8> for AtomicI8

fn from(v: i8) -> AtomicI8

impl<T> From<T> for Option<T>

fn from(val: T) -> Option<T>

impl From<u16> for u64

fn from(small: u16) -> u64

impl From<u8> for usize

fn from(small: u8) -> usize

impl From<i32> for i64

fn from(small: i32) -> i64

impl From<u16> for u128

fn from(small: u16) -> u128

impl From<i32> for AtomicI32

fn from(v: i32) -> AtomicI32

impl From<u16> for f64

fn from(small: u16) -> f64

impl From<u16> for u32

fn from(small: u16) -> u32

impl From<u8> for u64

fn from(small: u8) -> u64

impl From<i64> for AtomicI64

fn from(v: i64) -> AtomicI64

impl From<Infallible> for TryFromIntError

fn from(infallible: Infallible) -> TryFromIntError

impl From<i8> for i32

fn from(small: i8) -> i32

impl From<i32> for f64

fn from(small: i32) -> f64

impl From<u8> for u16

fn from(small: u8) -> u16

impl From<u16> for i32

fn from(small: u16) -> i32

impl<T> From<T> for UnsafeCell<T>

fn from(t: T) -> UnsafeCell<T>

impl<T> From<Unique<T>> for NonNull<T> where
    T: ?Sized, 

fn from(unique: Unique<T>) -> NonNull<T>

impl From<i16> for AtomicI16

fn from(v: i16) -> AtomicI16

impl From<i8> for f64

fn from(small: i8) -> f64

impl From<u8> for i64

fn from(small: u8) -> i64

impl From<i64> for i128

fn from(small: i64) -> i128

impl From<i16> for i32

fn from(small: i16) -> i32

impl From<i8> for i128

fn from(small: i8) -> i128

impl From<isize> for AtomicIsize

fn from(v: isize) -> AtomicIsize

impl From<u64> for AtomicU64

fn from(v: u64) -> AtomicU64

impl From<i16> for f32

fn from(small: i16) -> f32

impl From<i8> for isize

fn from(small: i8) -> isize

impl From<i16> for i128

fn from(small: i16) -> i128

impl From<f32> for f64

fn from(small: f32) -> f64

impl From<u8> for u32

fn from(small: u8) -> u32

impl From<u32> for u128

fn from(small: u32) -> u128

impl From<u32> for f64

fn from(small: u32) -> f64

impl From<u64> for i128

fn from(small: u64) -> i128

impl From<i8> for i64

fn from(small: i8) -> i64

impl<'a, T> From<&'a T> for NonZero<*const T> where
    T: ?Sized, 

fn from(reference: &'a T) -> NonZero<*const T>

impl From<u32> for i128

fn from(small: u32) -> i128

impl<'a, T> From<&'a T> for Unique<T> where
    T: ?Sized, 

fn from(reference: &'a T) -> Unique<T>

impl From<u32> for u64

fn from(small: u32) -> u64

impl From<i8> for f32

fn from(small: i8) -> f32

impl<T> From<T> for Cell<T>

fn from(t: T) -> Cell<T>

impl<T> From<*mut T> for AtomicPtr<T>

fn from(p: *mut T) -> AtomicPtr<T>

impl From<u16> for AtomicU16

fn from(v: u16) -> AtomicU16

impl From<u8> for f32

fn from(small: u8) -> f32

impl From<u8> for i16

fn from(small: u8) -> i16

impl From<u64> for u128

fn from(small: u64) -> u128

impl From<i16> for i64

fn from(small: i16) -> i64

impl From<u8> for char

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

fn from(i: u8) -> char

impl From<usize> for AtomicUsize

fn from(v: usize) -> AtomicUsize

impl From<i32> for i128

fn from(small: i32) -> i128

impl From<i8> for i16

fn from(small: i8) -> i16

impl From<u8> for AtomicU8

fn from(v: u8) -> AtomicU8

impl<'a, T> From<&'a mut T> for Unique<T> where
    T: ?Sized, 

fn from(reference: &'a mut T) -> Unique<T>

impl From<u8> for i32

fn from(small: u8) -> i32

impl From<u32> for i64

fn from(small: u32) -> i64

impl From<u8> for u128

fn from(small: u8) -> u128

impl From<i16> for f64

fn from(small: i16) -> f64

impl<'a, T> From<NonNull<T>> for Unique<T> where
    T: ?Sized, 

fn from(p: NonNull<T>) -> Unique<T>

impl<'a, T> From<&'a mut T> for NonZero<*const T> where
    T: ?Sized, 

fn from(reference: &'a mut T) -> NonZero<*const T>

impl From<u16> for i64

fn from(small: u16) -> i64

impl From<char> for u32

fn from(c: char) -> u32

impl<'a, T> From<&'a T> for NonNull<T> where
    T: ?Sized, 

fn from(reference: &'a T) -> NonNull<T>

impl From<u16> for f32

fn from(small: u16) -> f32

impl<'a, T> From<&'a mut T> for NonZero<*mut T> where
    T: ?Sized, 

fn from(reference: &'a mut T) -> NonZero<*mut T>

impl From<u32> for AtomicU32

fn from(v: u32) -> AtomicU32

impl From<u16> for i128

fn from(small: u16) -> i128

impl<'a, T> From<&'a mut T> for NonNull<T> where
    T: ?Sized, 

fn from(reference: &'a mut T) -> NonNull<T>

impl From<u8> for f64

fn from(small: u8) -> f64

impl From<u8> for i128

fn from(small: u8) -> i128

impl From<bool> for AtomicBool

fn from(b: bool) -> AtomicBool

impl From<Box<str>> for Box<[u8]>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

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

fn from(s: &'a [T]) -> Cow<'a, [T]>

impl From<Box<str>> for String

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

impl From<String> for Arc<str>

fn from(v: String) -> Arc<str>

impl From<String> for Vec<u8>

Important traits for Vec<u8>

impl Write for Vec<u8>

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

impl<T> From<Vec<T>> for BinaryHeap<T> where
    T: Ord, 

fn from(vec: Vec<T>) -> BinaryHeap<T>

impl<'a, T> From<&'a mut [T]> for Vec<T> where
    T: Clone, 

Important traits for Vec<u8>

impl Write for Vec<u8>

fn from(s: &'a mut [T]) -> Vec<T>

impl<'a> From<&'a str> for Box<str>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

fn from(s: &'a str) -> Box<str>

impl<T> From<Vec<T>> for Box<[T]>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

fn from(v: Vec<T>) -> Box<[T]>

impl<T> From<Vec<T>> for Arc<[T]>

fn from(v: Vec<T>) -> Arc<[T]>

impl<T> From<Box<T>> for Arc<T> where
    T: ?Sized, 

fn from(v: Box<T>) -> Arc<T>

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

Important traits for Vec<u8>

impl Write for Vec<u8>

fn from(s: Cow<'a, [T]>) -> Vec<T>

impl<'a> From<&'a str> for Arc<str>

fn from(v: &str) -> Arc<str>

impl<'a> From<Cow<'a, str>> for String

fn from(s: Cow<'a, str>) -> String

impl<T> From<Vec<T>> for VecDeque<T>

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

impl<'a, T> From<&'a [T]> for Box<[T]> where
    T: Copy, 

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

fn from(slice: &'a [T]) -> Box<[T]>

impl From<String> for Box<str>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

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

impl<'a> From<String> for Cow<'a, str>

fn from(s: String) -> Cow<'a, str>

impl<T> From<T> for Box<T>

Important traits for Box<W>

impl<W> Write for Box<W> where
    W: Write + ?Sized, impl<R> Read for Box<R> where
    R: Read + ?Sized, impl<I> Iterator for Box<I> where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

fn from(t: T) -> Box<T>

impl<'a> From<&'a str> for String

fn from(s: &'a str) -> String

impl<'a> From<&'a str> for Vec<u8>

Important traits for Vec<u8>

impl Write for Vec<u8>

fn from(s: &'a str) -> Vec<u8>

impl<T> From<VecDeque<T>> for Vec<T>

Important traits for Vec<u8>

impl Write for Vec<u8>

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

impl<T> From<T> for Arc<T>

fn from(t: T) -> Arc<T>

impl<'a, T> From<&'a [T]> for Arc<[T]> where
    T: Clone, 

fn from(v: &[T]) -> Arc<[T]>

impl<T> From<BinaryHeap<T>> for Vec<T>

Important traits for Vec<u8>

impl Write for Vec<u8>

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

impl<'a> From<&'a str> for Cow<'a, str>

fn from(s: &'a str) -> Cow<'a, str>

impl<T> From<Box<[T]>> for Vec<T>

Important traits for Vec<u8>

impl Write for Vec<u8>

fn from(s: Box<[T]>) -> Vec<T>

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

fn from(v: Vec<T>) -> Cow<'a, [T]>

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

Important traits for Vec<u8>

impl Write for Vec<u8>

fn from(s: &'a [T]) -> Vec<T>

Implementors

• impl<'a> From<&'a CStr> for Rc<CStr>
• impl From<CString> for Rc<CStr>
• impl From<OsString> for Rc<OsStr>
• impl From<PathBuf> for Rc<Path>
• impl<'a> From<&'a Path> for Rc<Path>
• impl<'a> From<&'a OsStr> for Rc<OsStr>
• impl<T> From<T> for RefCell<T>
• impl<T> From<T> for T
• impl<T> From<T> for Rc<T>
• impl<'a, T> From<&'a [T]> for Rc<[T]> where
    T: Clone, 
• impl<T> From<Box<T>> for Rc<T> where
    T: ?Sized, 
• impl From<String> for Rc<str>
• impl<T> From<Vec<T>> for Rc<[T]>
• impl<'a> From<&'a str> for Rc<str>
• impl<'a> From<Rc<*mut Vari>> for &'a mut Vari
• impl<'a> From<Rc<*mut Vari>> for &'a Vari
• impl From<Real> for VariData