Add SysError/WinError constructors that take a HintFmt-producing function#15359
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Ericson2314 merged 1 commit intomasterfrom Feb 27, 2026
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Add SysError/WinError constructors that take a HintFmt-producing function#15359Ericson2314 merged 1 commit intomasterfrom
SysError/WinError constructors that take a HintFmt-producing function#15359Ericson2314 merged 1 commit intomasterfrom
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…g function
This allows capturing the current value/result of
`errno`/`GetLastError()` before constructing the error message. Useful
when the error message construction itself might clobber the error code
(e.g., calling `descriptorToPath()`).
Usage:
```
throw NativeSysError([&] { return HintFmt("msg %s", foo()); });
```
The error code is captured when the exception is constructed, then the
lambda is called to produce the `HintFmt`.
Also fix the Windows build
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Motivation
This allows capturing
errno/GetLastError()before constructing the error message. Useful when the error message construction itself might clobber the error code (e.g., callingdescriptorToPath()).Also fix the Windows build
Context
Usage:
The error code is captured when the exception is constructed, then the lambda is called to produce the
HintFmt.Add 👍 to pull requests you find important.
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