Trait geng::prelude::TryFrom

pub trait TryFrom<T>: Sized {
    type Error;

    // Required method
    fn try_from(value: T) -> Result<Self, Self::Error>;
}

Simple and safe type conversions that may fail in a controlled way under some circumstances. It is the reciprocal of TryInto.

This is useful when you are doing a type conversion that may trivially succeed but may also need special handling. For example, there is no way to convert an i64 into an i32 using the From trait, because an i64 may contain a value that an i32 cannot represent and so the conversion would lose data. This might be handled by truncating the i64 to an i32 or by simply returning i32::MAX, or by some other method. The From trait is intended for perfect conversions, so the TryFrom trait informs the programmer when a type conversion could go bad and lets them decide how to handle it.

Generic Implementations

• TryFrom<T> for U implies TryInto<U> for T
• try_from is reflexive, which means that TryFrom<T> for T is implemented and cannot fail – the associated Error type for calling T::try_from() on a value of type T is Infallible. When the ! type is stabilized Infallible and ! will be equivalent.

TryFrom<T> can be implemented as follows:

struct GreaterThanZero(i32);

impl TryFrom<i32> for GreaterThanZero {
    type Error = &'static str;

    fn try_from(value: i32) -> Result<Self, Self::Error> {
        if value <= 0 {
            Err("GreaterThanZero only accepts values greater than zero!")
        } else {
            Ok(GreaterThanZero(value))
        }
    }
}

Examples

As described, i32 implements TryFrom<i64>:

let big_number = 1_000_000_000_000i64;
// Silently truncates `big_number`, requires detecting
// and handling the truncation after the fact.
let smaller_number = big_number as i32;
assert_eq!(smaller_number, -727379968);

// Returns an error because `big_number` is too big to
// fit in an `i32`.
let try_smaller_number = i32::try_from(big_number);
assert!(try_smaller_number.is_err());

// Returns `Ok(3)`.
let try_successful_smaller_number = i32::try_from(3);
assert!(try_successful_smaller_number.is_ok());

Required Associated Types

type Error

The type returned in the event of a conversion error.

Required Methods

fn try_from(value: T) -> Result<Self, Self::Error>

Performs the conversion.

Object Safety

This trait is not object safe.

Implementors

impl TryFrom<&str> for geng::Key

type Error = ParseError

impl TryFrom<&str> for MouseButton

type Error = ParseError

impl TryFrom<&str> for Uuid

type Error = Error

impl TryFrom<&str> for Alphabet

type Error = ParseAlphabetError

impl TryFrom<&str> for Regex

type Error = Error

impl TryFrom<&str> for Regex

type Error = Error

impl TryFrom<&str> for ServerName

Attempt to make a ServerName from a string by parsing it as a DNS name.

type Error = InvalidDnsNameError

impl TryFrom<&str> for Theme

type Error = ()

impl TryFrom<&String> for PathAndQuery

type Error = InvalidUri

impl TryFrom<&[u8]> for ReasonPhrase

type Error = InvalidReasonPhrase

impl TryFrom<&[u8]> for Tag

type Error = Unspecified

impl TryFrom<char> for u8

Maps a char with code point in U+0000..=U+00FF to a byte in 0x00..=0xFF with same value, failing if the code point is greater than U+00FF.

See impl From<u8> for char for details on the encoding.

type Error = TryFromCharError

impl TryFrom<char> for u16

Maps a char with code point in U+0000..=U+FFFF to a u16 in 0x0000..=0xFFFF with same value, failing if the code point is greater than U+FFFF.

This corresponds to the UCS-2 encoding, as specified in ISO/IEC 10646:2003.

type Error = TryFromCharError

impl TryFrom<f32> for RealImpl<f32>

type Error = &'static str

impl TryFrom<f64> for RealImpl<f64>

type Error = &'static str

impl TryFrom<i8> for u8

type Error = TryFromIntError

impl TryFrom<i8> for u16

type Error = TryFromIntError

impl TryFrom<i8> for u32

type Error = TryFromIntError

impl TryFrom<i8> for u64

type Error = TryFromIntError

impl TryFrom<i8> for u128

type Error = TryFromIntError

impl TryFrom<i8> for usize

type Error = TryFromIntError

impl TryFrom<i8> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<i16> for i8

type Error = TryFromIntError

impl TryFrom<i16> for u8

type Error = TryFromIntError

impl TryFrom<i16> for u16

type Error = TryFromIntError

impl TryFrom<i16> for u32

type Error = TryFromIntError

impl TryFrom<i16> for u64

type Error = TryFromIntError

impl TryFrom<i16> for u128

type Error = TryFromIntError

impl TryFrom<i16> for usize

type Error = TryFromIntError

impl TryFrom<i16> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<i32> for i8

type Error = TryFromIntError

impl TryFrom<i32> for i16

type Error = TryFromIntError

impl TryFrom<i32> for isize

type Error = TryFromIntError

impl TryFrom<i32> for u8

type Error = TryFromIntError

impl TryFrom<i32> for u16

type Error = TryFromIntError

impl TryFrom<i32> for u32

type Error = TryFromIntError

impl TryFrom<i32> for u64

type Error = TryFromIntError

impl TryFrom<i32> for u128

type Error = TryFromIntError

impl TryFrom<i32> for usize

type Error = TryFromIntError

impl TryFrom<i32> for NonZeroI32

type Error = TryFromIntError

impl TryFrom<i32> for DumpableBehavior

type Error = Errno

impl TryFrom<i32> for SecureComputingMode

type Error = Errno

impl TryFrom<i32> for SockType

type Error = Errno

impl TryFrom<i32> for TimingMethod

type Error = Errno

impl TryFrom<i64> for i8

type Error = TryFromIntError

impl TryFrom<i64> for i16

type Error = TryFromIntError

impl TryFrom<i64> for i32

type Error = TryFromIntError

impl TryFrom<i64> for isize

type Error = TryFromIntError

impl TryFrom<i64> for u8

type Error = TryFromIntError

impl TryFrom<i64> for u16

type Error = TryFromIntError

impl TryFrom<i64> for u32

type Error = TryFromIntError

impl TryFrom<i64> for u64

type Error = TryFromIntError

impl TryFrom<i64> for u128

type Error = TryFromIntError

impl TryFrom<i64> for usize

type Error = TryFromIntError

impl TryFrom<i64> for NonZeroI64

type Error = TryFromIntError

impl TryFrom<i128> for i8

type Error = TryFromIntError

impl TryFrom<i128> for i16

type Error = TryFromIntError

impl TryFrom<i128> for i32

type Error = TryFromIntError

impl TryFrom<i128> for i64

type Error = TryFromIntError

impl TryFrom<i128> for isize

type Error = TryFromIntError

impl TryFrom<i128> for u8

type Error = TryFromIntError

impl TryFrom<i128> for u16

type Error = TryFromIntError

impl TryFrom<i128> for u32

type Error = TryFromIntError

impl TryFrom<i128> for u64

type Error = TryFromIntError

impl TryFrom<i128> for u128

type Error = TryFromIntError

impl TryFrom<i128> for usize

type Error = TryFromIntError

impl TryFrom<i128> for NonZeroI128

type Error = TryFromIntError

impl TryFrom<isize> for i8

type Error = TryFromIntError

impl TryFrom<isize> for i16

type Error = TryFromIntError

impl TryFrom<isize> for i32

type Error = TryFromIntError

impl TryFrom<isize> for i64

type Error = TryFromIntError

impl TryFrom<isize> for i128

type Error = TryFromIntError

impl TryFrom<isize> for u8

type Error = TryFromIntError

impl TryFrom<isize> for u16

type Error = TryFromIntError

impl TryFrom<isize> for u32

type Error = TryFromIntError

impl TryFrom<isize> for u64

type Error = TryFromIntError

impl TryFrom<isize> for u128

type Error = TryFromIntError

impl TryFrom<isize> for usize

type Error = TryFromIntError

impl TryFrom<isize> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<u8> for i8

type Error = TryFromIntError

impl TryFrom<u8> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<u8> for Action

type Error = u8

impl TryFrom<u8> for Channels

type Error = Error

impl TryFrom<u8> for ColorSpace

type Error = Error

impl TryFrom<u8> for RevocationReason

type Error = Error

impl TryFrom<u8> for State

type Error = u8

impl TryFrom<u8> for SysCallUserDispatchFastSwitch

type Error = Errno

impl TryFrom<u16> for i8

type Error = TryFromIntError

impl TryFrom<u16> for i16

type Error = TryFromIntError

impl TryFrom<u16> for isize

type Error = TryFromIntError

impl TryFrom<u16> for u8

type Error = TryFromIntError

impl TryFrom<u16> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<u16> for StatusCode

type Error = InvalidStatusCode

impl TryFrom<u16> for PatternID

type Error = PatternIDError

impl TryFrom<u16> for PatternID

type Error = PatternIDError

impl TryFrom<u16> for SmallIndex

type Error = SmallIndexError

impl TryFrom<u16> for StateID

type Error = StateIDError

impl TryFrom<u16> for StateID

type Error = StateIDError

impl TryFrom<u32> for ugli::error::Error

type Error = TryFromPrimitiveError<Error>

impl TryFrom<u32> for char

type Error = CharTryFromError

impl TryFrom<u32> for i8

type Error = TryFromIntError

impl TryFrom<u32> for i16

type Error = TryFromIntError

impl TryFrom<u32> for i32

type Error = TryFromIntError

impl TryFrom<u32> for isize

type Error = TryFromIntError

impl TryFrom<u32> for u8

type Error = TryFromIntError

impl TryFrom<u32> for u16

type Error = TryFromIntError

impl TryFrom<u32> for usize

type Error = TryFromIntError

impl TryFrom<u32> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<u32> for AdaptiveSyncState

type Error = ()

impl TryFrom<u32> for Anchor

type Error = ()

impl TryFrom<u32> for Anchor

type Error = ()

impl TryFrom<u32> for Attrib

type Error = ()

impl TryFrom<u32> for Axis

type Error = ()

impl TryFrom<u32> for AxisRelativeDirection

type Error = ()

impl TryFrom<u32> for AxisSource

type Error = ()

impl TryFrom<u32> for ButtonState

type Error = ()

impl TryFrom<u32> for ButtonState

type Error = ()

impl TryFrom<u32> for ButtonState

type Error = ()

impl TryFrom<u32> for ButtonState

type Error = ()

impl TryFrom<u32> for CancelReason

type Error = ()

impl TryFrom<u32> for Capability

type Error = ()

impl TryFrom<u32> for Capability

type Error = ()

impl TryFrom<u32> for Capability

type Error = ()

impl TryFrom<u32> for Capability

type Error = ()

impl TryFrom<u32> for Capability

type Error = ()

impl TryFrom<u32> for Capability

type Error = ()

impl TryFrom<u32> for ChangeCause

type Error = ()

impl TryFrom<u32> for ConstraintAdjustment

type Error = ()

impl TryFrom<u32> for ContentHint

type Error = ()

impl TryFrom<u32> for ContentHint

type Error = ()

impl TryFrom<u32> for ContentHint

type Error = ()

impl TryFrom<u32> for ContentHint

type Error = ()

impl TryFrom<u32> for ContentPurpose

type Error = ()

impl TryFrom<u32> for ContentPurpose

type Error = ()

impl TryFrom<u32> for ContentPurpose

type Error = ()

impl TryFrom<u32> for ContentPurpose

type Error = ()

impl TryFrom<u32> for CoreSchedulingScope

type Error = Errno

impl TryFrom<u32> for DndAction

type Error = ()

impl TryFrom<u32> for Enablement

type Error = ()

impl TryFrom<u32> for EndianMode

type Error = Errno

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Error

type Error = ()

impl TryFrom<u32> for Flags

type Error = ()

impl TryFrom<u32> for Flags

type Error = ()

impl TryFrom<u32> for Flags

type Error = ()

impl TryFrom<u32> for FloatingPointMode

type Error = Errno

impl TryFrom<u32> for Format

type Error = ()

impl TryFrom<u32> for FullscreenMethod

type Error = ()

impl TryFrom<u32> for Gravity

type Error = ()

impl TryFrom<u32> for InputPanelVisibility

type Error = ()

impl TryFrom<u32> for Key

type Error = ()

impl TryFrom<u32> for KeyState

type Error = ()

impl TryFrom<u32> for KeyboardInteractivity

type Error = ()

impl TryFrom<u32> for KeymapFormat

type Error = ()

impl TryFrom<u32> for Kind

type Error = ()

impl TryFrom<u32> for Layer

type Error = ()

impl TryFrom<u32> for Lifetime

type Error = ()

impl TryFrom<u32> for Location

type Error = ()

impl TryFrom<u32> for MachineCheckMemoryCorruptionKillPolicy

type Error = Errno

impl TryFrom<u32> for Mode

type Error = ()

impl TryFrom<u32> for Mode

type Error = ()

impl TryFrom<u32> for Mode

type Error = ()

impl TryFrom<u32> for Mode

type Error = ()

impl TryFrom<u32> for Mode

type Error = ()

impl TryFrom<u32> for Mode

type Error = ()

impl TryFrom<u32> for Mode

type Error = ()

impl TryFrom<u32> for PanelBehavior

type Error = ()

impl TryFrom<u32> for PatternID

type Error = PatternIDError

impl TryFrom<u32> for PatternID

type Error = PatternIDError

impl TryFrom<u32> for Pointer

type Error = ()

impl TryFrom<u32> for Position

type Error = ()

impl TryFrom<u32> for PreeditStyle

type Error = ()

impl TryFrom<u32> for PreeditStyle

type Error = ()

impl TryFrom<u32> for PreeditStyle

type Error = ()

impl TryFrom<u32> for PresentMethod

type Error = ()

impl TryFrom<u32> for PresentMode

type Error = ()

impl TryFrom<u32> for PresentationHint

type Error = ()

impl TryFrom<u32> for Resize

type Error = ()

impl TryFrom<u32> for ResizeEdge

type Error = ()

impl TryFrom<u32> for RgbRange

type Error = ()

impl TryFrom<u32> for RgbRange

type Error = ()

impl TryFrom<u32> for Role

type Error = ()

impl TryFrom<u32> for Shape

type Error = ()

impl TryFrom<u32> for ShowDesktop

type Error = ()

impl TryFrom<u32> for SmallIndex

type Error = SmallIndexError

impl TryFrom<u32> for Source

type Error = ()

impl TryFrom<u32> for Source

type Error = ()

impl TryFrom<u32> for SpeculationFeature

type Error = Errno

impl TryFrom<u32> for State

type Error = ()

impl TryFrom<u32> for State

type Error = ()

impl TryFrom<u32> for State

type Error = ()

impl TryFrom<u32> for State

type Error = ()

impl TryFrom<u32> for StateID

type Error = StateIDError

impl TryFrom<u32> for StateID

type Error = StateIDError

impl TryFrom<u32> for Subpixel

type Error = ()

impl TryFrom<u32> for Subpixel

type Error = ()

impl TryFrom<u32> for Subpixel

type Error = ()

impl TryFrom<u32> for TextDirection

type Error = ()

impl TryFrom<u32> for TextDirection

type Error = ()

impl TryFrom<u32> for TextDirection

type Error = ()

impl TryFrom<u32> for TimeStampCounterReadability

type Error = Errno

impl TryFrom<u32> for TrancheFlags

type Error = ()

impl TryFrom<u32> for Transform

type Error = ()

impl TryFrom<u32> for Transform

type Error = ()

impl TryFrom<u32> for Transform

type Error = ()

impl TryFrom<u32> for Transient

type Error = ()

impl TryFrom<u32> for Type

type Error = ()

impl TryFrom<u32> for Type

type Error = ()

impl TryFrom<u32> for Type

type Error = ()

impl TryFrom<u32> for UpdateState

type Error = ()

impl TryFrom<u32> for VrrPolicy

type Error = ()

impl TryFrom<u32> for VrrPolicy

type Error = ()

impl TryFrom<u32> for VrrPolicy

type Error = ()

impl TryFrom<u32> for VrrPolicy

type Error = ()

impl TryFrom<u32> for WmCapabilities

type Error = ()

impl TryFrom<u64> for i8

type Error = TryFromIntError

impl TryFrom<u64> for i16

type Error = TryFromIntError

impl TryFrom<u64> for i32

type Error = TryFromIntError

impl TryFrom<u64> for i64

type Error = TryFromIntError

impl TryFrom<u64> for isize

type Error = TryFromIntError

impl TryFrom<u64> for u8

type Error = TryFromIntError

impl TryFrom<u64> for u16

type Error = TryFromIntError

impl TryFrom<u64> for u32

type Error = TryFromIntError

impl TryFrom<u64> for usize

type Error = TryFromIntError

impl TryFrom<u64> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<u64> for PatternID

type Error = PatternIDError

impl TryFrom<u64> for PatternID

type Error = PatternIDError

impl TryFrom<u64> for SmallIndex

type Error = SmallIndexError

impl TryFrom<u64> for StateID

type Error = StateIDError

impl TryFrom<u64> for StateID

type Error = StateIDError

impl TryFrom<u128> for i8

type Error = TryFromIntError

impl TryFrom<u128> for i16

type Error = TryFromIntError

impl TryFrom<u128> for i32

type Error = TryFromIntError

impl TryFrom<u128> for i64

type Error = TryFromIntError

impl TryFrom<u128> for i128

type Error = TryFromIntError

impl TryFrom<u128> for isize

type Error = TryFromIntError

impl TryFrom<u128> for u8

type Error = TryFromIntError

impl TryFrom<u128> for u16

type Error = TryFromIntError

impl TryFrom<u128> for u32

type Error = TryFromIntError

impl TryFrom<u128> for u64

type Error = TryFromIntError

impl TryFrom<u128> for usize

type Error = TryFromIntError

impl TryFrom<u128> for NonZeroU128

type Error = TryFromIntError

impl TryFrom<usize> for i8

type Error = TryFromIntError

impl TryFrom<usize> for i16

type Error = TryFromIntError

impl TryFrom<usize> for i32

type Error = TryFromIntError

impl TryFrom<usize> for i64

type Error = TryFromIntError

impl TryFrom<usize> for i128

type Error = TryFromIntError

impl TryFrom<usize> for isize

type Error = TryFromIntError

impl TryFrom<usize> for u8

type Error = TryFromIntError

impl TryFrom<usize> for u16

type Error = TryFromIntError

impl TryFrom<usize> for u32

type Error = TryFromIntError

impl TryFrom<usize> for u64

type Error = TryFromIntError

impl TryFrom<usize> for u128

type Error = TryFromIntError

impl TryFrom<usize> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<usize> for Alignment

type Error = TryFromIntError

impl TryFrom<usize> for PatternID

type Error = PatternIDError

impl TryFrom<usize> for PatternID

type Error = PatternIDError

impl TryFrom<usize> for SmallIndex

type Error = SmallIndexError

impl TryFrom<usize> for StateID

type Error = StateIDError

impl TryFrom<usize> for StateID

type Error = StateIDError

impl TryFrom<Error> for Errno

type Error = Error

impl TryFrom<Error> for Errno

type Error = Error

impl TryFrom<Error> for Errno

type Error = Error

impl TryFrom<String> for HeaderName

type Error = InvalidHeaderName

impl TryFrom<String> for HeaderValue

type Error = InvalidHeaderValue

impl TryFrom<String> for Authority

type Error = InvalidUri

impl TryFrom<String> for PathAndQuery

type Error = InvalidUri

impl TryFrom<String> for Uri

type Error = InvalidUri

impl TryFrom<String> for DnsName

type Error = InvalidDnsNameError

impl TryFrom<String> for ReasonPhrase

type Error = InvalidReasonPhrase

impl TryFrom<String> for Regex

type Error = Error

impl TryFrom<String> for Regex

type Error = Error

impl TryFrom<Vec<u8>> for HeaderName

type Error = InvalidHeaderName

impl TryFrom<Vec<u8>> for HeaderValue

type Error = InvalidHeaderValue

impl TryFrom<Vec<u8>> for Authority

type Error = InvalidUri

impl TryFrom<Vec<u8>> for Uuid

type Error = Error

impl TryFrom<Vec<u8>> for ReasonPhrase

type Error = InvalidReasonPhrase

impl TryFrom<NonZeroI8> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroI8> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroI8> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroI8> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<NonZeroI8> for NonZeroU128

type Error = TryFromIntError

impl TryFrom<NonZeroI8> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroI16> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroI16> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroI16> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroI16> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroI16> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<NonZeroI16> for NonZeroU128

type Error = TryFromIntError

impl TryFrom<NonZeroI16> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroU128

type Error = TryFromIntError

impl TryFrom<NonZeroI32> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroI32

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroU128

type Error = TryFromIntError

impl TryFrom<NonZeroI64> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroI32

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroI64

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroU128

type Error = TryFromIntError

impl TryFrom<NonZeroI128> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroI32

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroI64

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroI128

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroU128

type Error = TryFromIntError

impl TryFrom<NonZeroIsize> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroU8> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroU16> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroU16> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroU16> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<NonZeroU16> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroU32> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroU32> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroU32> for NonZeroI32

type Error = TryFromIntError

impl TryFrom<NonZeroU32> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<NonZeroU32> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroU32> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroU32> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroI32

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroI64

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroU64> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroI32

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroI64

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroI128

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<NonZeroU128> for NonZeroUsize

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroI8

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroI16

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroI32

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroI64

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroI128

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroIsize

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroU8

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroU16

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroU32

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroU64

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for NonZeroU128

type Error = TryFromIntError

impl TryFrom<NonZeroUsize> for Alignment

type Error = TryFromIntError

impl TryFrom<TcpListener> for Async<TcpListener>

type Error = Error

impl TryFrom<TcpListener> for Async<TcpListener>

type Error = Error

impl TryFrom<TcpListener> for TcpListener

type Error = Error

impl TryFrom<TcpStream> for Async<TcpStream>

type Error = Error

impl TryFrom<TcpStream> for Async<TcpStream>

type Error = Error

impl TryFrom<TcpStream> for TcpStream

type Error = Error

impl TryFrom<UdpSocket> for Async<UdpSocket>

type Error = Error

impl TryFrom<UdpSocket> for Async<UdpSocket>

type Error = Error

impl TryFrom<UdpSocket> for UdpSocket

type Error = Error

impl TryFrom<UnixDatagram> for Async<UnixDatagram>

type Error = Error

impl TryFrom<UnixDatagram> for Async<UnixDatagram>

type Error = Error

impl TryFrom<UnixDatagram> for UnixDatagram

type Error = Error

impl TryFrom<UnixListener> for Async<UnixListener>

type Error = Error

impl TryFrom<UnixListener> for Async<UnixListener>

type Error = Error

impl TryFrom<UnixListener> for UnixListener

type Error = Error

impl TryFrom<UnixStream> for Async<UnixStream>

type Error = Error

impl TryFrom<UnixStream> for Async<UnixStream>

type Error = Error

impl TryFrom<UnixStream> for UnixStream

type Error = Error

impl TryFrom<SystemTime> for Time

type Error = SystemTimeError

impl TryFrom<Parts> for Uri

type Error = InvalidUriParts

impl TryFrom<Request> for http::request::Request<Body>

type Error = Error

impl TryFrom<Bytes> for ReasonPhrase

type Error = InvalidReasonPhrase

impl TryFrom<Connect> for Setup

type Error = ConnectError

impl TryFrom<Layer> for Layer

type Error = UnknownLayer

impl TryFrom<PlainMessage> for Message

Parses a plaintext message into a well-typed [Message].

A [PlainMessage] must contain plaintext content. Encrypted content should be stored in an [OpaqueMessage] and decrypted before being stored into a [PlainMessage].

type Error = Error

impl TryFrom<TcpListener> for std::net::tcp::TcpListener

type Error = Error

impl TryFrom<TcpStream> for std::net::tcp::TcpStream

type Error = Error

impl TryFrom<UdpSocket> for std::net::udp::UdpSocket

type Error = Error

impl TryFrom<UnixDatagram> for std::os::unix::net::datagram::UnixDatagram

type Error = Error

impl TryFrom<UnixListener> for std::os::unix::net::listener::UnixListener

type Error = Error

impl TryFrom<UnixStream> for std::os::unix::net::stream::UnixStream

type Error = Error

impl<'a> TryFrom<&'a str> for HeaderName

type Error = InvalidHeaderName

impl<'a> TryFrom<&'a str> for HeaderValue

type Error = InvalidHeaderValue

impl<'a> TryFrom<&'a str> for Method

type Error = InvalidMethod

impl<'a> TryFrom<&'a str> for StatusCode

type Error = InvalidStatusCode

impl<'a> TryFrom<&'a str> for Authority

type Error = InvalidUri

impl<'a> TryFrom<&'a str> for PathAndQuery

type Error = InvalidUri

impl<'a> TryFrom<&'a str> for Scheme

type Error = InvalidUri

impl<'a> TryFrom<&'a str> for Uri

type Error = InvalidUri

impl<'a> TryFrom<&'a str> for Url

type Error = ParseError

impl<'a> TryFrom<&'a String> for HeaderName

type Error = InvalidHeaderName

impl<'a> TryFrom<&'a String> for HeaderValue

type Error = InvalidHeaderValue

impl<'a> TryFrom<&'a String> for Uri

type Error = InvalidUri

impl<'a> TryFrom<&'a OsStr> for &'a str

type Error = Utf8Error

impl<'a> TryFrom<&'a Uri> for Uri

type Error = Error

impl<'a> TryFrom<&'a Certificate> for ParsedCertificate<'a>

type Error = Error

impl<'a> TryFrom<&'a [u8]> for HeaderName

type Error = InvalidHeaderName

impl<'a> TryFrom<&'a [u8]> for HeaderValue

type Error = InvalidHeaderValue

impl<'a> TryFrom<&'a [u8]> for Method

type Error = InvalidMethod

impl<'a> TryFrom<&'a [u8]> for StatusCode

type Error = InvalidStatusCode

impl<'a> TryFrom<&'a [u8]> for Authority

type Error = InvalidUri

impl<'a> TryFrom<&'a [u8]> for PathAndQuery

type Error = InvalidUri

impl<'a> TryFrom<&'a [u8]> for Scheme

type Error = InvalidUri

impl<'a> TryFrom<&'a [u8]> for Uri

type Error = InvalidUri

impl<'a> TryFrom<&'a [u8]> for EndEntityCert<'a>

type Error = Error

impl<'a> TryFrom<Vec<u8>> for PathAndQuery

type Error = InvalidUri

impl<'a> TryFrom<Vec<u8>> for Uri

type Error = InvalidUri

impl<'a, K, V, T> TryFrom<&'a HashMap<K, V>> for HeaderMap<T>

where K: Eq + Hash, HeaderName: TryFrom<&'a K>, <HeaderName as TryFrom<&'a K>>::Error: Into<Error>, T: TryFrom<&'a V>, <T as TryFrom<&'a V>>::Error: Into<Error>,

Try to convert a HashMap into a HeaderMap.

Examples

use std::collections::HashMap;
use std::convert::TryInto;
use http::HeaderMap;

let mut map = HashMap::new();
map.insert("X-Custom-Header".to_string(), "my value".to_string());

let headers: HeaderMap = (&map).try_into().expect("valid headers");
assert_eq!(headers["X-Custom-Header"], "my value");

type Error = Error

impl<'a, T, const N: usize> TryFrom<&'a [T]> for &'a [T; N]

Tries to create an array ref &[T; N] from a slice ref &[T]. Succeeds if slice.len() == N.

let bytes: [u8; 3] = [1, 0, 2];

let bytes_head: &[u8; 2] = <&[u8; 2]>::try_from(&bytes[0..2]).unwrap();
assert_eq!(1, u16::from_le_bytes(*bytes_head));

let bytes_tail: &[u8; 2] = bytes[1..3].try_into().unwrap();
assert_eq!(512, u16::from_le_bytes(*bytes_tail));

type Error = TryFromSliceError

impl<'a, T, const N: usize> TryFrom<&'a mut [T]> for &'a mut [T; N]

Tries to create a mutable array ref &mut [T; N] from a mutable slice ref &mut [T]. Succeeds if slice.len() == N.

let mut bytes: [u8; 3] = [1, 0, 2];

let bytes_head: &mut [u8; 2] = <&mut [u8; 2]>::try_from(&mut bytes[0..2]).unwrap();
assert_eq!(1, u16::from_le_bytes(*bytes_head));

let bytes_tail: &mut [u8; 2] = (&mut bytes[1..3]).try_into().unwrap();
assert_eq!(512, u16::from_le_bytes(*bytes_tail));

type Error = TryFromSliceError

impl<'a, const CAP: usize> TryFrom<&'a str> for ArrayString<CAP>

type Error = CapacityError<&'a str>

impl<'a, const CAP: usize> TryFrom<Arguments<'a>> for ArrayString<CAP>

type Error = CapacityError<Error>

impl<T> TryFrom<&str> for Rgba<T>

where T: ColorComponent,

type Error = Error

impl<T> TryFrom<String> for Rgba<T>

where T: ColorComponent,

type Error = Error

impl<T> TryFrom<OwnedFd> for Async<T>

where T: AsFd + From<OwnedFd>,

type Error = Error

impl<T> TryFrom<OwnedFd> for Async<T>

where T: AsRawFd + From<OwnedFd>,

type Error = Error

impl<T> TryFrom<Request<T>> for reqwest::async_impl::request::Request

where T: Into<Body>,

type Error = Error

impl<T> TryFrom<Async<T>> for OwnedFd

where T: Into<OwnedFd>,

type Error = Error

impl<T> TryFrom<Async<T>> for OwnedFd

where T: Into<OwnedFd>,

type Error = Error

impl<T, A> TryFrom<&[T]> for ArrayVec<A>

where T: Clone + Default, A: Array<Item = T>,

type Error = TryFromSliceError

impl<T, A, const N: usize> TryFrom<Vec<T, A>> for [T; N]

where A: Allocator,

type Error = Vec<T, A>

impl<T, A, const N: usize> TryFrom<Arc<[T], A>> for Arc<[T; N], A>

where A: Allocator + Clone,

type Error = Arc<[T], A>

impl<T, U> TryFrom<U> for T

where U: Into<T>,

type Error = Infallible

impl<T, const CAP: usize> TryFrom<&[T]> for arrayvec::arrayvec::ArrayVec<T, CAP>

where T: Clone,

Try to create an ArrayVec from a slice. This will return an error if the slice was too big to fit.

use arrayvec::ArrayVec;
use std::convert::TryInto as _;

let array: ArrayVec<_, 4> = (&[1, 2, 3] as &[_]).try_into().unwrap();
assert_eq!(array.len(), 3);
assert_eq!(array.capacity(), 4);

type Error = CapacityError

impl<T, const N: usize> TryFrom<&[T]> for [T; N]

where T: Copy,

Tries to create an array [T; N] by copying from a slice &[T]. Succeeds if slice.len() == N.

let bytes: [u8; 3] = [1, 0, 2];

let bytes_head: [u8; 2] = <[u8; 2]>::try_from(&bytes[0..2]).unwrap();
assert_eq!(1, u16::from_le_bytes(bytes_head));

let bytes_tail: [u8; 2] = bytes[1..3].try_into().unwrap();
assert_eq!(512, u16::from_le_bytes(bytes_tail));

type Error = TryFromSliceError

impl<T, const N: usize> TryFrom<&[T]> for Simd<T, N>

where LaneCount<N>: SupportedLaneCount, T: SimdElement,

type Error = TryFromSliceError

impl<T, const N: usize> TryFrom<&mut [T]> for [T; N]

where T: Copy,

Tries to create an array [T; N] by copying from a mutable slice &mut [T]. Succeeds if slice.len() == N.

let mut bytes: [u8; 3] = [1, 0, 2];

let bytes_head: [u8; 2] = <[u8; 2]>::try_from(&mut bytes[0..2]).unwrap();
assert_eq!(1, u16::from_le_bytes(bytes_head));

let bytes_tail: [u8; 2] = (&mut bytes[1..3]).try_into().unwrap();
assert_eq!(512, u16::from_le_bytes(bytes_tail));

type Error = TryFromSliceError

impl<T, const N: usize> TryFrom<&mut [T]> for Simd<T, N>

where LaneCount<N>: SupportedLaneCount, T: SimdElement,

type Error = TryFromSliceError

impl<T, const N: usize> TryFrom<Box<[T]>> for Box<[T; N]>

type Error = Box<[T]>

impl<T, const N: usize> TryFrom<Vec<T>> for Box<[T; N]>

type Error = Vec<T>

impl<T, const N: usize> TryFrom<Rc<[T]>> for Rc<[T; N]>

type Error = Rc<[T]>