2 unstable releases
0.2.0 | Sep 4, 2019 |
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0.1.0 | Sep 4, 2019 |
#1758 in Rust patterns
1,637 downloads per month
14KB
try_or_wrap
This crate provides a macro similar to the old try!
macro, or to the ?
, except it wraps
the error in something else.
This is useful if you want to use a ?
for easily returning say, invalid input errors,
but you can't do so because you have an additional Result
level for handling internal errors of a different nature.
This macro allows you to do so:
fn foo(input: Input) -> Result<Result<FinalOutput, InvalidInputError>, DatabaseError> {
let validated_input: ValidatedInput = try_or_wrap!(validate_input_with_database(input)?, Ok);
Ok(Ok(do_stuff_with_validated_input(validated_input)?))
}
fn validate_input_with_database(input: Input) -> Result<Result<ValidatedInput, InvalidInputError>, DatabaseError>;
lib.rs
:
This crate provides a macro similar to the old try!
macro, or to the ?
, except it wraps
the error in something else.
This is useful if you want to use a ?
for easily returning say, invalid input errors,
but you can't do so because you have an additional Result
level for handling internal errors of a different nature.
This macro allows you to do so:
fn foo(input: Input) -> Result<Result<FinalOutput, InvalidInputError>, DatabaseError> {
let validated_input: ValidatedInput = try_or_wrap!(validate_input_with_database(input)?, Ok);
Ok(Ok(do_stuff_with_validated_input(validated_input)?))
}
fn validate_input_with_database(input: Input) -> Result<Result<ValidatedInput, InvalidInputError>, DatabaseError>;