On this page
Enum std::env::VarError
pub enum VarError {
NotPresent,
NotUnicode(OsString),
}
The error type for operations interacting with environment variables. Possibly returned from env::var()
.
Variants
NotPresent
The specified environment variable was not present in the current process’s environment.
NotUnicode(OsString)
The specified environment variable was found, but it did not contain valid unicode data. The found data is returned as a payload of this variant.
Trait Implementations
impl Clone for VarError
fn clone(&self) -> VarError
Returns a copy of the value. Read more
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from
source
. Read more
impl Debug for VarError
fn fmt(&self, f: &mut Formatter<'_>) -> Result
Formats the value using the given formatter. Read more
impl Display for VarError
fn fmt(&self, f: &mut Formatter<'_>) -> Result
Formats the value using the given formatter. Read more
impl Error for VarError
fn description(&self) -> &str
👎Deprecated since 1.42.0: use the Display impl or to_string()
fn source(&self) -> Option<&(dyn Error + 'static)>
The lower-level source of this error, if any. Read more
fn cause(&self) -> Option<&dyn Error>
👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting
fn provide<'a>(&'a self, request: &mut Request<'a>)
🔬This is a nightly-only experimental API. (
error_generic_member_access
#99301)
Provides type based access to context intended for error reports. Read more
impl PartialEq for VarError
fn eq(&self, other: &VarError) -> bool
This method tests for
self
and other
values to be equal, and is used by ==
.
fn ne(&self, other: &Rhs) -> bool
This method tests for
!=
. The default implementation is almost always sufficient, and should not be overridden without very good reason.
impl Eq for VarError
impl StructuralEq for VarError
impl StructuralPartialEq for VarError
Auto Trait Implementations
impl RefUnwindSafe for VarError
impl Send for VarError
impl Sync for VarError
impl Unpin for VarError
impl UnwindSafe for VarError
Blanket Implementations
impl<T> Any for T
where
T: 'static + ?Sized,
impl<T> Borrow<T> for T
where
T: ?Sized,
impl<T> BorrowMut<T> for T
where
T: ?Sized,
impl<T> From<T> for T
fn from(t: T) -> T
Returns the argument unchanged.
impl<T, U> Into<U> for T
where
U: From<T>,
fn into(self) -> U
Calls U::from(self)
.
That is, this conversion is whatever the implementation of From<T> for U
chooses to do.
impl<T> ToOwned for T
where
T: Clone,
type Owned = T
The resulting type after obtaining ownership.
fn to_owned(&self) -> T
Creates owned data from borrowed data, usually by cloning. Read more
fn clone_into(&self, target: &mut T)
Uses borrowed data to replace owned data, usually by cloning. Read more
impl<T> ToString for T
where
T: Display + ?Sized,
impl<T, U> TryFrom<U> for T
where
U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
Performs the conversion.
impl<T, U> TryInto<U> for T
where
U: TryFrom<T>,
type Error = <U as TryFrom<T>>::Error
The type returned in the event of a conversion error.
fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>
Performs the conversion.
© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/env/enum.VarError.html