Enum ModeFlag 

pub enum ModeFlag {
    In,
    Out,
    Either,
}

Per-argument mode flag for a relation declared via (mode …).

Variants

In

+input: caller must supply a ground argument here.

Out

-output: the relation is expected to produce a value here.

Either

*either: no directionality constraint.

Implementations

impl ModeFlag

pub fn from_token(token: &str) -> Option<Self>

Trait Implementations

impl Clone for ModeFlag

fn clone(&self) -> ModeFlag

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ModeFlag

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

Formats the value using the given formatter.

impl PartialEq for ModeFlag

fn eq(&self, other: &ModeFlag) -> 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 ModeFlag

impl Eq for ModeFlag

impl StructuralPartialEq for ModeFlag