Enum Capability 

pub enum Capability {
    SpawnArgs,
    PaneYurai,
    Freio,
}

One named thing a daemon build can do. Each variant names a field or a behaviour a caller can gate on — never a release, never a date.

The wire form is a string, deliberately: a client that meets a daemon advertising a capability from a newer vocabulary must ignore the name it doesn’t know, not fail to decode the frame. Strings make that free; a serialized enum would make it a hard error.

Variants

SpawnArgs

The daemon reads the args field on Request::NewSession, Request::NewWindow and Request::SplitPane, and passes it to the child as argv[1..].

A daemon without this reads the request fine — args is #[serde(default)] and no type sets deny_unknown_fields, so the key is simply dropped — and spawns the bare program. That silent drop is the failure this whole module exists to convert into a legible refusal.

PaneYurai

The daemon stamps TearPane::yurai at spawn from the connection’s shutai, so a pane records WHAT KIND of actor created it.

Gates provenance READS (tear list showing which panes an agent drives) and is useful with or without a brake. A daemon without it reports every pane as Yurai::Unknown — which is honest, and is also exactly why freio cannot brake Unknown.

Freio

The daemon reads Request::SetFreio / Request::GetFreio.

Independent of PaneYurai in one direction only: freio WITHOUT yurai is meaningless (nothing to filter on), yurai without freio is useful on its own. They ship in that order and a client can tell.

This capability is the reason a panic button cannot fail silently: an old daemon would drop SetFreio as an unknown variant and answer a legible Rejected, but the CLI must require() it FIRST so the operator sees a typed refusal rather than a wire error on the one command where “nothing happened” is unacceptable.

Implementations

impl Capability

pub const ALL: &'static [Capability]

Every capability name this build’s vocabulary knows. Not the same thing as what a given daemon advertises — see Capability::advertised.

pub fn wire_name(self) -> &'static str

The on-wire name. Kebab-case, names the field or behaviour.

pub fn from_wire(s: &str) -> Option<Self>

Parse a wire name back to a typed capability. None for a name from a vocabulary this build doesn’t have — which is the expected outcome when an older client meets a newer daemon, and must stay a quiet miss rather than an error.

pub fn advertised(self) -> bool

Does this build of the daemon implement the capability?

The exhaustive match is the seal: adding a Capability variant without deciding this is error[E0004]: non-exhaustive patterns, so no capability can land unclassified.

Trait Implementations

impl Clone for Capability

fn clone(&self) -> Capability

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Capability

impl Debug for Capability

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

Formats the value using the given formatter.

impl Eq for Capability

impl Hash for Capability

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Capability

fn cmp(&self, other: &Capability) -> 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 Capability

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

Equality operator ==.

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

Inequality operator !=.

impl PartialOrd for Capability

fn partial_cmp(&self, other: &Capability) -> 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 StructuralPartialEq for Capability