[−][src]Crate tracerr

Custom compile time captured error tracing.

Provides tools for making error output more informative. It adds ability to capture custom error trace frames (at compile time) and to display errors with the final captured trace.

Usage

The common rule:

Use macro to capture trace frame in the invocation place.

use tracerr::Traced;

let err = tracerr::new!("my error"); // captures frame

let res: Result<(), _> = Err(err)
    .map_err(tracerr::wrap!()); // captures frame

let err: Traced<&'static str> = res.unwrap_err();
assert_eq!(
    format!("{}\n{}", err, err.trace()),
    r"my error
error trace:
rust_out
  at src/lib.rs:6
rust_out
  at src/lib.rs:9",
);

let (val, trace) = err.into_parts();
assert_eq!(
    format!("{}\n{}", val, trace),
    r"my error
error trace:
rust_out
  at src/lib.rs:6
rust_out
  at src/lib.rs:9",
);

Macros

from_and_wrap	Provides a closure, which captures new `Frame` in the invocation place, applies required `From` implementation for the given error and wraps it into `Traced` wrapper containing this `Frame`. If the error is a `Traced` already then just growth its `Trace` with the captured `Frame`.
map_from_and_new	Captures new `Frame` in the invocation place and wraps the given error into `Traced` wrapper containing this `Frame` with applying required `From` implementation for the wrapped error. If the error is a `Traced` already then just applies `From` implementation and growth its `Trace` with the captured `Frame`.
map_from_and_wrap	Provides a closure, which captures new `Frame` in the invocation place for the given `Traced` wrapper and applies required `From` implementation for the wrapped error.
new	Captures new `Frame` in the invocation place and wraps the given error into `Traced` wrapper containing this `Frame`. If the error is a `Traced` already then just growth its `Trace` with the captured `Frame`.
new_frame	Captures and returns new `Frame` in the macro invocation place.
wrap	Provides a closure, which captures new `Frame` in the invocation place and wraps the given error into `Traced` wrapper containing this `Frame`. If the error is a `Traced` already then just growth its `Trace` with the captured `Frame`.

Structs

Frame	Captured frame of `Trace`.
Trace	Trace composed from captured `Frame`s.
Traced	Transparent wrapper for an error which holds captured error trace along with it.

Statics

DEFAULT_FRAMES_CAPACITY

Default capacity for Trace buffer initialization.

Traits

WrapTraced

Trait for wrapping errors into a Traced wrapper and growing Trace inside.

Functions

map_from

Maps value of error wrapped in Traced with its From implementation.