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#[unstable(feature = "try_trait", issue = "42327")]
#[cfg_attr(bootstrap, rustc_on_unimplemented(
on(all(
any(from_method="from_error", from_method="from_ok"),
from_desugaring="QuestionMark"),
message="the `?` operator can only be used in a \
function that returns `Result` or `Option` \
(or another type that implements `{Try}`)",
label="cannot use the `?` operator in a function that returns `{Self}`"),
on(all(from_method="into_result", from_desugaring="QuestionMark"),
message="the `?` operator can only be applied to values \
that implement `{Try}`",
label="the `?` operator cannot be applied to type `{Self}`")
))]
#[cfg_attr(not(bootstrap), rustc_on_unimplemented(
on(all(
any(from_method="from_error", from_method="from_ok"),
from_desugaring="QuestionMark"),
message="the `?` operator can only be used in {ItemContext} \
that returns `Result` or `Option` \
(or another type that implements `{Try}`)",
label="cannot use the `?` operator in {ItemContext} that returns `{Self}`"),
on(all(from_method="into_result", from_desugaring="QuestionMark"),
message="the `?` operator can only be applied to values \
that implement `{Try}`",
label="the `?` operator cannot be applied to type `{Self}`")
))]
#[doc(alias = "?")]
pub trait Try {
#[unstable(feature = "try_trait", issue = "42327")]
type Ok;
#[unstable(feature = "try_trait", issue = "42327")]
type Error;
#[unstable(feature = "try_trait", issue = "42327")]
fn into_result(self) -> Result<Self::Ok, Self::Error>;
#[unstable(feature = "try_trait", issue = "42327")]
fn from_error(v: Self::Error) -> Self;
#[unstable(feature = "try_trait", issue = "42327")]
fn from_ok(v: Self::Ok) -> Self;
}