Struct std::panic::Location
pub struct Location<'a> { /* private fields */ }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");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>pub fn caller() -> &'static Location<'static>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());pub fn file(&self) -> &strReturns 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");pub fn line(&self) -> u32Returns 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");pub fn column(&self) -> u32Returns 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");Trait Implementations
impl<'a> Clone for Location<'a>fn clone(&self) -> Location<'a>
Returns a copy of the value. Read more
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from
source. Read more
impl<'a> Debug for Location<'a>fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
Formats the value using the given formatter. Read more
impl Display for Location<'_>fn fmt(&self, formatter: &mut Formatter<'_>) -> Result<(), Error>
Formats the value using the given formatter. Read more
impl<'a> Hash for Location<'a>fn hash<__H>(&self, state: &mut __H)
where
__H: Hasher,fn hash_slice<H>(data: &[Self], state: &mut H)
where
H: Hasher,
Self: Sized,impl<'a> Ord for Location<'a>fn cmp(&self, other: &Location<'a>) -> Orderingfn max(self, other: Self) -> Self
where
Self: Sized,
Compares and returns the maximum of two values. Read more
fn min(self, other: Self) -> Self
where
Self: Sized,
Compares and returns the minimum of two values. Read more
fn clamp(self, min: Self, max: Self) -> Self
where
Self: Sized + PartialOrd,
Restrict a value to a certain interval. Read more
impl<'a> PartialEq for Location<'a>fn eq(&self, other: &Location<'a>) -> 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<'a> PartialOrd for Location<'a>fn partial_cmp(&self, other: &Location<'a>) -> Option<Ordering>fn lt(&self, other: &Rhs) -> boolfn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for
self and other) and is used by the <= operator. Read more
fn gt(&self, other: &Rhs) -> boolfn ge(&self, other: &Rhs) -> bool
This method tests greater than or equal to (for
self and other) and is used by the >= operator. Read more
impl<'a> Copy for Location<'a>impl<'a> Eq for Location<'a>impl<'a> StructuralEq for Location<'a>impl<'a> StructuralPartialEq for Location<'a>Auto Trait Implementations
impl<'a> RefUnwindSafe for Location<'a>impl<'a> Send for Location<'a>impl<'a> Sync for Location<'a>impl<'a> Unpin for Location<'a>impl<'a> UnwindSafe for Location<'a>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 Tfn from(t: T) -> TReturns the argument unchanged.
impl<T, U> Into<U> for T
where
U: From<T>,fn into(self) -> UCalls 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/panic/struct.Location.html