Struct std::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");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>
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) -> &str
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");pub fn line(&self) -> u32
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");pub fn column(&self) -> u32
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");Trait Implementations
impl<'a> Clone for Location<'a>
pub 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>
pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
Formats the value using the given formatter. Read more
impl<'_> Display for Location<'_>
pub fn fmt(&self, formatter: &mut Formatter<'_>) -> Result<(), Error>
Formats the value using the given formatter. Read more
impl<'a> Hash for Location<'a>
impl<'a> Ord for Location<'a>
pub fn cmp(&self, other: &Location<'a>) -> Ordering
fn max(self, other: Self) -> Self
Compares and returns the maximum of two values. Read more
fn min(self, other: Self) -> Self
Compares and returns the minimum of two values. Read more
fn clamp(self, min: Self, max: Self) -> Self
Restrict a value to a certain interval. Read more
impl<'a> PartialEq<Location<'a>> for Location<'a>
pub fn eq(&self, other: &Location<'a>) -> bool
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
This method tests for !=.
impl<'a> PartialOrd<Location<'a>> for Location<'a>
pub fn partial_cmp(&self, other: &Location<'a>) -> Option<Ordering>
This method returns an ordering between self and other values if one exists. Read more
fn lt(&self, other: &Rhs) -> bool
This method tests less than (for self and other) and is used by the < operator. Read more
fn 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) -> bool
This method tests greater than (for self and other) and is used by the > operator. Read more
fn 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> From<T> for T
pub fn from(t: T) -> T
Performs the conversion.
pub fn into(self) -> U
Performs the conversion.
type Owned = T
The resulting type after obtaining ownership.
pub fn to_owned(&self) -> T
Creates owned data from borrowed data, usually by cloning. Read more
pub fn clone_into(&self, target: &mut T)
toowned_clone_into #41263)recently added
Uses borrowed data to replace owned data, usually by cloning. Read more
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>
Performs the conversion.
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>
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