std::panic::Location - Rust
Description: API documentation for the Rust `Location` struct in crate `std`.
Keywords: rust, rustlang, rust-lang, Location

# 1.10.0[−][src]Struct std::panic::Location

    #[lang = "panic_location"]pub struct Location<'a> { /* fields omitted */ }

A struct containing information about the location of a panic.

This structure is created by `PanicInfo::location()`.

# Examples

ⓘ

    use std::panic;

    panic::set_hook(Box::new(|panic_info| {
        if let Some(location) = panic_info.location() {
            println!("panic occurred in file '{}' at line {}", location.file(), location.line());
        } else {
            println!("panic occurred but can't get location information...");
        }
    }));

    panic!("Normal panic");

Run

# Comparisons

Comparisons for equality and ordering are made in file, line, then column priority. Files are compared as strings, not `Path`, which could be unexpected. See `Location::file`'s documentation for more discussion.

## Implementations

### `impl<'a> Location<'a>`[src]

#### `pub fn caller() -> &'static Location<'static>`1.46.0[src]

Returns the source location of the caller of this function. If that function's caller is annotated then its call location will be returned, and so on up the stack to the first call within a non-tracked function body.

# Examples

    use std::panic::Location;

    /// Returns the [`Location`] at which it is called.
    #[track_caller]
    fn get_caller_location() -> &'static Location<'static> {
        Location::caller()
    }

    /// Returns a [`Location`] from within this function's definition.
    fn get_just_one_location() -> &'static Location<'static> {
        get_caller_location()
    }

    let fixed_location = get_just_one_location();
    assert_eq!(fixed_location.file(), file!());
    assert_eq!(fixed_location.line(), 14);
    assert_eq!(fixed_location.column(), 5);

    // running the same untracked function in a different location gives us the same result
    let second_fixed_location = get_just_one_location();
    assert_eq!(fixed_location.file(), second_fixed_location.file());
    assert_eq!(fixed_location.line(), second_fixed_location.line());
    assert_eq!(fixed_location.column(), second_fixed_location.column());

    let this_location = get_caller_location();
    assert_eq!(this_location.file(), file!());
    assert_eq!(this_location.line(), 28);
    assert_eq!(this_location.column(), 21);

    // running the tracked function in a different location produces a different value
    let another_location = get_caller_location();
    assert_eq!(this_location.file(), another_location.file());
    assert_ne!(this_location.line(), another_location.line());
    assert_ne!(this_location.column(), another_location.column());

Run

### `impl<'a> Location<'a>`[src]

#### `pub fn file(&self) -> &str`[src]

Returns the name of the source file from which the panic originated.

# `&str`, not `&Path`

The returned name refers to a source path on the compiling system, but it isn't valid to represent this directly as a `&Path`. The compiled code may run on a different system with a different `Path` implementation than the system providing the contents and this library does not currently have a different "host path" type.

The most surprising behavior occurs when "the same" file is reachable via multiple paths in the module system (usually using the `#[path = "..."]` attribute or similar), which can cause what appears to be identical code to return differing values from this function.

# Cross-compilation

This value is not suitable for passing to `Path::new` or similar constructors when the host platform and target platform differ.

# Examples

ⓘ

    use std::panic;

    panic::set_hook(Box::new(|panic_info| {
        if let Some(location) = panic_info.location() {
            println!("panic occurred in file '{}'", location.file());
        } else {
            println!("panic occurred but can't get location information...");
        }
    }));

    panic!("Normal panic");

Run

#### `pub fn line(&self) -> u32`[src]

Returns the line number from which the panic originated.

# Examples

ⓘ

    use std::panic;

    panic::set_hook(Box::new(|panic_info| {
        if let Some(location) = panic_info.location() {
            println!("panic occurred at line {}", location.line());
        } else {
            println!("panic occurred but can't get location information...");
        }
    }));

    panic!("Normal panic");

Run

#### `pub fn column(&self) -> u32`1.25.0[src]

Returns the column from which the panic originated.

# Examples

ⓘ

    use std::panic;

    panic::set_hook(Box::new(|panic_info| {
        if let Some(location) = panic_info.location() {
            println!("panic occurred at column {}", location.column());
        } else {
            println!("panic occurred but can't get location information...");
        }
    }));

    panic!("Normal panic");

Run

## Trait Implementations

### `impl<'a> Clone for Location<'a>`[src]

#### `pub fn clone(&self) -> Location<'a>`[src]

Returns a copy of the value. Read more

#### `pub fn clone_from(&mut self, source: &Self)`1.0.0[src]

Performs copy-assignment from `source`. Read more

### `impl<'a> Copy for Location<'a>`[src]

### `impl<'a> Debug for Location<'a>`[src]

#### `pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter. Read more

### `impl<'_> Display for Location<'_>`1.26.0[src]

#### `pub fn fmt(&self, formatter: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter. Read more

### `impl<'a> Eq for Location<'a>`[src]

### `impl<'a> Hash for Location<'a>`[src]

#### `pub fn hash<__H>(&self, state: &mut __H) where
__H: Hasher,` [src]

Feeds this value into the given `Hasher`. Read more

#### `pub fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,` 1.3.0[src]

Feeds a slice of this type into the given `Hasher`. Read more

### `impl<'a> Ord for Location<'a>`[src]

#### `pub fn cmp(&self, other: &Location<'a>) -> Ordering`[src]

This method returns an `Ordering` between `self` and `other`. Read more

#### `#[must_use]pub fn max(self, other: Self) -> Self`1.21.0[src]

Compares and returns the maximum of two values. Read more

#### `#[must_use]pub fn min(self, other: Self) -> Self`1.21.0[src]

Compares and returns the minimum of two values. Read more

#### `#[must_use]pub fn clamp(self, min: Self, max: Self) -> Self`1.50.0[src]

Restrict a value to a certain interval. Read more

### `impl<'a> PartialEq<Location<'a>> for Location<'a>`[src]

#### `pub fn eq(&self, other: &Location<'a>) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `pub fn ne(&self, other: &Location<'a>) -> bool`[src]

This method tests for `!=`.

### `impl<'a> PartialOrd<Location<'a>> for Location<'a>`[src]

#### `pub fn partial_cmp(&self, other: &Location<'a>) -> Option<Ordering>`[src]

This method returns an ordering between `self` and `other` values if one exists. Read more

#### `pub fn lt(&self, other: &Location<'a>) -> bool`[src]

This method tests less than (for `self` and `other`) and is used by the `<` operator. Read more

#### `pub fn le(&self, other: &Location<'a>) -> bool`[src]

This method tests less than or equal to (for `self` and `other`) and is used by the `<=` operator. Read more

#### `pub fn gt(&self, other: &Location<'a>) -> bool`[src]

This method tests greater than (for `self` and `other`) and is used by the `>` operator. Read more

#### `pub fn ge(&self, other: &Location<'a>) -> bool`[src]

This method tests greater than or equal to (for `self` and `other`) and is used by the `>=` operator. Read more

### `impl<'a> StructuralEq for Location<'a>`[src]

### `impl<'a> StructuralPartialEq for Location<'a>`[src]

## Auto Trait Implementations

### `impl<'a> RefUnwindSafe for Location<'a>`[src]

### `impl<'a> Send for Location<'a>`[src]

### `impl<'a> Sync for Location<'a>`[src]

### `impl<'a> Unpin for Location<'a>`[src]

### `impl<'a> UnwindSafe for Location<'a>`[src]

## Blanket Implementations

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `pub fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow(&self) -> &Tⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[src]

Immutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow_mut(&mut self) -> &mut Tⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[src]

Mutably borrows from an owned value. Read more

### `impl<T> From<T> for T`[src]

#### `pub fn from(t: T) -> T`[src]

Performs the conversion.

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `pub fn into(self) -> U`[src]

Performs the conversion.

### `impl<T> ToOwned for T where
T: Clone,` [src]

#### `type Owned = T`

The resulting type after obtaining ownership.

#### `pub fn to_owned(&self) -> T`[src]

Creates owned data from borrowed data, usually by cloning. Read more

#### `pub fn clone_into(&self, target: &mut T)`[src]

🔬 This is a nightly-only experimental API. (`toowned_clone_into` #41263)

recently added

Uses borrowed data to replace owned data, usually by cloning. Read more

### `impl<T> ToString for T where
T: Display + ?Sized,` [src]

#### `pub default fn to_string(&self) -> String`[src]

Converts the given value to a `String`. Read more

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

#### `type Error = <U as TryFrom<T>>::Error`

The type returned in the event of a conversion error.

#### `pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.