Struct Saver 

pub struct Saver<T> { /* private fields */ }

Converts a value to and from the string form preferences store.

A saver is deliberately explicit rather than derived: the stored form is a compatibility surface, and the framework will not guess it for you.

Implementations

impl<T> Saver<T>

pub fn new( save: impl Fn(&T) -> String + 'static, restore: impl Fn(&str) -> Option<T> + 'static, ) -> Self

Builds a saver from a pair of conversions.

pub fn save(&self, value: &T) -> String

The stored form of value.

pub fn restore(&self, stored: &str) -> Option<T>

The value stored represents, or None when it cannot be read — a stored form written by an older build, or a corrupted entry.

impl<T> Saver<T>

where T: Display + FromStr + 'static,

pub fn of_display() -> Self

The saver for a type that already round-trips through Display and FromStr — numbers, booleans, strings, enums with a parse impl.