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add track_caller attribute to map_err and ok_or/_else #142093

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add track_caller attribute to map_err and ok_or/_else #142093

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2 changes: 2 additions & 0 deletions library/core/src/option.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -1305,6 +1305,7 @@ impl<T> Option<T> {
/// assert_eq!(x.ok_or(0), Err(0));
/// ```
#[inline]
#[track_caller]
#[stable(feature = "rust1", since = "1.0.0")]
pub fn ok_or<E>(self, err: E) -> Result<T, E> {
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Just curious: What's the reason to add track_caller on this function? ok_or does not panic nor call any user code that would track the caller. Or do you expect the Drop from E to track the caller? but that seems far fetched. Am I missing something or is this an oversight? (map_or_else seems like a better candidate)
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@yaahc yaahc Jun 30, 2025 •
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you're right, that's an oversight. The only one that matters is ok_or_else due to it taking a closure. Ill also look at adding it to map_or_else
match self {
Expand All @@ -1330,6 +1331,7 @@ impl<T> Option<T> {
/// assert_eq!(x.ok_or_else(|| 0), Err(0));
/// ```
#[inline]
#[track_caller]
#[stable(feature = "rust1", since = "1.0.0")]
pub fn ok_or_else<E, F>(self, err: F) -> Result<T, E>
where
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1 change: 1 addition & 0 deletions library/core/src/result.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -907,6 +907,7 @@ impl<T, E> Result<T, E> {
/// assert_eq!(x.map_err(stringify), Err("error code: 13".to_string()));
/// ```
#[inline]
#[track_caller]
#[stable(feature = "rust1", since = "1.0.0")]
pub fn map_err<F, O: FnOnce(E) -> F>(self, op: O) -> Result<T, F> {
match self {
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