SmartErr

SmartErr, an error handling library, introduces several convenient aproaches to define, raise and handle domain-specific errors in libraries and/or applications.

With SmartErr it is possible to:

• raise errors with raise and throw methods on regular types (numbers, strings, boolean, Option, Result, etc) as an error source. Look into Raising errors section to find out more details.
• define the exact set of errors emitted by the function or introduce global set for the public API (requires erorrset feature).

Quick overview

See this example below.

Raising or throwing errors

Sometimes functions may return simple types instead of Result. Library provides a set of methods to convert these types into Result based on the convention what values should be treated as an error:

Further actions depend on the function used to convert the value into Result:

throw - does NOT change error context. When the error state is detected, the value is mapped with the provided err_map function and returned as Err(err_map(original_value)). Otherwise, the original value is just wrapped into Result::Ok.

raise - CHANGES error context. When the error state is detected, the original value is wrapped into Result::Ok. Otherwise, the value is mapped with the provided ok_to_err_map function and returned as Err(ok_to_err_map(original_value)).

Defining errors

With errorset feature enabled, it is possible to define a set of errors emitted by the function. The errorset macro generates a new error type that contains all the errors from the function signature. You may find more details in the ErrorSet crate documentation.

SmartErr crate reexports ErrorSet crate, so you may use it functionality directly.