Enum Effect 

pub enum Effect {
    Allow,
    Ask,
    Deny,
}

What a rule does. Ordered by strictness: Allow < Ask < Deny.

The ordering is not decoration — it is how stacking two policies is defined. Policy::merge and Policy::contain take the max of the two defaults per act, so combining policies can only ever tighten them:

use io_harness::{Act, Effect, Policy};

assert!(Effect::Allow < Effect::Ask && Effect::Ask < Effect::Deny);

// A permissive overlay cannot loosen a base's asking default.
let combined = Policy::default().merge(Policy::permissive());
assert_eq!(combined.check(Act::Write, "anything-unmatched").effect, Effect::Ask);

The three effects also mean three different things at run time, and the middle one is the only one a human ever sees: Allow proceeds silently, Ask routes to the Approver, and Deny refuses without consulting anyone — a denied action never reaches an approver, so an ApproveAll cannot wave it through.

Variants

Allow

Proceed without asking.

Ask

Proceed only after a human approves.

Deny

Never proceed. Absolute across layers.

Trait Implementations

impl Clone for Effect

fn clone(&self) -> Effect

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Effect

impl Debug for Effect

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Effect

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for Effect

impl Ord for Effect

fn cmp(&self, other: &Effect) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Effect

fn eq(&self, other: &Effect) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for Effect

fn partial_cmp(&self, other: &Effect) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Effect

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Effect