std::result

Status: experimental

Data-last Result combinators for pipeline chaining: map, map_err, unwrap_or_else, etc.

API details and source

The implementation source contains the complete declarations and implementation notes. The table below lists canonical Gossamer call signatures; every item name links directly to its implementation file.

Item	Canonical signature or declaration	Description
and_then	fn and_then<T, E, U>(f: Fn(T) -> Result<U, E>, value: Result<T, E>) -> Result<U, E>	Chains a fallible step on the Ok payload.
err	fn err<T, E>(value: Result<T, E>) -> Option<E>	Err payload as an Option.
is_err	fn is_err<T, E>(value: Result<T, E>) -> bool	True for Err.
is_ok	fn is_ok<T, E>(value: Result<T, E>) -> bool	True for Ok.
map	fn map<T, E, U>(f: Fn(T) -> U, value: Result<T, E>) -> Result<U, E>	Transforms the Ok payload, Err passes through.
map_err	fn map_err<T, E, F>(f: Fn(E) -> F, value: Result<T, E>) -> Result<T, F>	Transforms the Err payload, Ok passes through.
ok	fn ok<T, E>(value: Result<T, E>) -> Option<T>	Ok payload as an Option.
or_else	fn or_else<T, E, F>(f: Fn(E) -> Result<T, F>, value: Result<T, E>) -> Result<T, F>	Recovers from Err with a fallback computation.
unwrap_or	fn unwrap_or<T, E>(fallback: T, value: Result<T, E>) -> T	Unwraps Ok with a fallback value for Err.
unwrap_or_else	fn unwrap_or_else<T, E>(f: Fn(E) -> T, value: Result<T, E>) -> T	Consumes the result, handling Err with a callback.