Struct Loc 

pub struct Loc<T> {
    pub value: T,
    pub span: Option<Span>,
}

Wrap any type with location information.

Loc is used to wrap a type to give it location information. It is a simple struct adjoining any given type to an Option<Span> and implementing Located and Locatable. This is meant to be done to types that are not under control and cannot be made to implement the traits directly because of the orphan instance rules, or because giving them a Span all the time does not make sense. Otherwise, deriving Located and Locatable directly using the associated derive macros is preferred.

It is often controverial to decide whether a Located type should compare equal accounting for its span or not. For this reason, Loc intentionally does not implement PartialEq nor Eq.

Fields

value: T

span: Option<Span>

Implementations

impl<T> Loc<T>

pub const fn new(value: T) -> Loc<T>

Creates a new Loc from a value without any Span information.

pub fn map<F, R>(self, f: F) -> Loc<R>

where F: FnOnce(T) -> R,

Transforms the inner value by applying the given function

Trait Implementations

impl<T: Clone> Clone for Loc<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug> Debug for Loc<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Default> Default for Loc<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T> Deref for Loc<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<T: Display> Display for Loc<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Eq> Eq for Loc<T>

impl<T: Error> Error for Loc<T>

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

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)

Provides type-based access to context intended for error reports.

impl<T> From<T> for Loc<T>

fn from(value: T) -> Self

Converts to this type from the input type.

impl<T: Hash> Hash for Loc<T>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T> Locatable for Loc<T>

type Located = Loc<T>

fn over(self, span: impl Into<Option<Span>>) -> Loc<T>

Turns self into an object of type Self::Located tracking the new span.

impl<T> Located for Loc<T>

fn span(&self) -> Option<Span>

Gets the Span tracked by the type.

impl<T: PartialEq> PartialEq for Loc<T>

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<T: PartialEq> StructuralPartialEq for Loc<T>