Crate scoped_error 

scoped_error - Context-aware error handling.

This library provides easy error context propagation without requiring wrapper types at each layer. Context (message + location) is attached directly to error types that implement WithContext.

Quick Start

For simple use cases, use scoped_error::Error with expect_error:

use scoped_error::{Error, expect_error};

fn do_work() -> Result<(), Error> {
    expect_error("Failed to do something", || {
        internal()?;
        Ok(())
    })
}

Use impl_context_error! to create custom context error types:

use scoped_error::{impl_context_error, expect_error};

impl_context_error!(MyError);

fn do_work() -> Result<(), MyError> {
    expect_error("Failed to do something", || {
        internal()?;
        Ok(())
    })
}

Core Concepts

• Context propagation: Attach context (message + source location) to errors
• No wrapper types: Context is stored directly in the error type
• Automatic location tracking: Uses #[track_caller] to capture call sites
• Error reports: Format full error chains with ErrorReport

Macros

impl_context_error

Implement context-aware error handling for a custom type.

Structs

Error

A convenient, ready-to-use error type with built-in context support.

ErrorReport

A formatted error report.

Frame

A single layer of error context.

Many

An error type that can have multiple simultaneous causes.

Traits

ErrorExt

Extension trait for std::error::Error.

WithContext

A trait for error types that can carry context information.

Functions

expect_error

Add context to errors, returning a custom error type.

expect_error_fn

Low-level function for adding context with a custom error constructor.