Trait MutContextPolicy 

pub trait MutContextPolicy<State> {
    // Required method
    fn default_mutate(
        &self,
        value: MutateValue<'_>,
        ctx: &mut MutateContext<'_, State>,
    ) -> Result<UnchangedOr<Any>>;
}

Default-recursion policy for MutateCallbacks::with_policy and MapWithContextPolicy.

ctx.default_maybe_inplace_mutate_result(value) continues to the next policy, then hooks or reflected fields; children re-enter callback dispatch. Policies share callback state and compose as (outer, inner). Restore user state before returning, including on errors; use MutateContext::with_def_region_kind for scoped definition regions.

Required Methods

fn default_mutate( &self, value: MutateValue<'_>, ctx: &mut MutateContext<'_, State>, ) -> Result<UnchangedOr<Any>>

Customize default descent, preserving the input permission and result marker.

Dyn Compatibility

This trait is dyn compatible.

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

Implementations on Foreign Types

impl<State, Outer: MutContextPolicy<State>, Inner: MutContextPolicy<State>> MutContextPolicy<State> for (Outer, Inner)

fn default_mutate( &self, value: MutateValue<'_>, ctx: &mut MutateContext<'_, State>, ) -> Result<UnchangedOr<Any>>

Implementors

impl<State> MutContextPolicy<State> for DefaultMutContextPolicy