Enum RefTransition 

#[repr(C, u8)]
pub enum RefTransition {
    None,
    Enter(RefId),
    Exit(RefId),
}

Marks a transition as entering or exiting a definition reference.

A transition can hold at most one RefTransition. Sequences like Enter(A) → Enter(B) require epsilon chains.

Layout: 1-byte discriminant + 1-byte padding + 2-byte RefId = 4 bytes, align 2.

Variants

None

No definition boundary crossing.

Enter(RefId)

Push call frame with return transitions.

For Enter(ref_id) transitions, successors have special structure:

• successors()[0]: definition entry point (where to jump)
• successors()[1..]: return transitions (stored in call frame)

Exit(RefId)

Pop frame, continue with stored return transitions.

Successors are ignored—returns come from the call frame pushed at Enter.

Implementations

impl RefTransition

pub fn is_none(self) -> bool

Returns true if this is None.

pub fn ref_id(self) -> Option<RefId>

Returns the ref ID if this is Enter or Exit.

Trait Implementations

impl Clone for RefTransition

fn clone(&self) -> RefTransition

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RefTransition

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

Formats the value using the given formatter.

impl Default for RefTransition

fn default() -> RefTransition

Returns the “default value” for a type.

impl PartialEq for RefTransition

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for RefTransition

impl Eq for RefTransition

impl StructuralPartialEq for RefTransition