Trait FromValue 

pub trait FromValue:
    Sized
    + Clone
    + Send
    + Sync
    + 'static
    + Sealed {
    type Out<'a>;
}

A type an expression can resolve to.

Sealed: the implementations are OwnedDataValue (lent as Cow<OwnedDataValue>), String (Cow<str>; a result that is not a string is its compact JSON), u64 and i64 (themselves: an integer, or a whole float, in the type’s range; above i64::MAX an integer is read as a float and may round; anything else is an error), f64 (itself: any finite number, the only kind JSON carries; anything else is an error), bool (itself; anything else is an error) and Path (Cow<Path>; a string parsed as a path).

Required Associated Types

type Out<'a>

What an evaluation hands back: a folded constant borrowed from the expression, a dynamic result owned.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl FromValue for OwnedDataValue

type Out<'a> = Cow<'a, OwnedDataValue>

impl FromValue for String

type Out<'a> = Cow<'a, str>

impl FromValue for bool

type Out<'a> = bool

impl FromValue for f64

type Out<'a> = f64

impl FromValue for i64

type Out<'a> = i64

impl FromValue for u64

type Out<'a> = u64

Implementors

impl FromValue for Path

type Out<'a> = Cow<'a, Path>