Enum Phrase

pub enum Phrase {
    BooleanQuery(PhraseBooleanQuery),
    InstanceQuery(PhraseInstanceQuery),
    Create(PhraseCreate),
    Terminate(PhraseTerminate),
    Obfuscate(PhraseObfuscate),
    Trigger(PhraseTrigger),
    AtomicFact(PhraseAtomicFact),
    CompositeFact(PhraseCompositeFact),
    Placeholder(PhrasePlaceholder),
    Predicate(PhrasePredicate),
    Event(PhraseEvent),
    Act(PhraseAct),
    Duty(PhraseDuty),
    Extend(PhraseExtend),
}

Represents an eFLINT statement, essentially.

Variants

BooleanQuery(PhraseBooleanQuery)

Defines a boolean query, e.g.,

? has-voted(Bob, Amy)

InstanceQuery(PhraseInstanceQuery)

Defines an instance query, e.g.,

?- has-voted(voter, Amy)

Create(PhraseCreate)

Postulates a certain fact to be true, e.g.,

+citizen(Amy).

Terminate(PhraseTerminate)

Postulates a certain fact to be false, e.g.,

-citizen(Amy).

Obfuscate(PhraseObfuscate)

Removes the postulation for a certain fact, falling back to its derived value, e.g.,

~citizen(Amy).

Trigger(PhraseTrigger)

Triggers an Event or an Act, e.g.,

vote(Amy, Bob).

AtomicFact(PhraseAtomicFact)

Defines a Fact that has atomic construction, e.g.,

Fact citizen Identified by String.

CompositeFact(PhraseCompositeFact)

Defines a Fact that has composite fields, e.g.,

Fact voter Identified by citizen.

Placeholder(PhrasePlaceholder)

Defines a Placeholder to create type aliases, e.g.,

Placeholder civilian For citizen.

Predicate(PhrasePredicate)

Defines a Predicate that can be used to “prepare” queries, e.g.,:

Predicate vote-concluded When Not(Exists citizen : voter(citizen) && !has-voted(citizen)).

This includes invariants, which are checked after every derivation procedure and can trigger violations when becoming false, e.g.,

Invariant at-most-one-winner When Not(Exists winner, winner' : winner != winner').

Event(PhraseEvent)

Defines an Event that can be used to automatically postulate facts, e.g.,:

Event fire Obfuscates vote.

Act(PhraseAct)

Defines an Act that can be used to automatically postulate facts while noting it was instantiated by a particular actor, e.g.:

Act murder
  Actor citizen1
  Related to citizen2
  Terminates citizen2

Duty(PhraseDuty)

Defines a Duty that can be violated when certain conditions are (not) met, e.g.:

Duty must-vote
  Holder citizen
  Claimant administrator
  Enforced by not-voted.

Extend(PhraseExtend)

Defines an extension to an existing type, e.g.:

Extend Duty duty-to-vote
  Conditioned by can-vote(voter).

Implementations

impl Phrase

pub fn subclass(&self) -> PhraseSubclass

Returns the phrase subclass for this phrase.

Returns

A PhraseSubclass describing the class of this data.

Trait Implementations

impl Clone for Phrase

fn clone(&self) -> Phrase

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Phrase

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Phrase

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl EnumDebug for Phrase

fn type_name() -> &'static str

Returns the static name of the type used for EnumDebug-printing.

fn variant_names() -> &'static [&'static str]

Returns all variants in the trait as a list of names.

fn variant_name(&self) -> &'static str

Returns the static name of the variant.

fn variant(&self) -> EnumDebugFormatter<'_, Self>

Returns a formatter for this enum that writes its variant name.

fn variants() -> Copied<Iter<'static, &'static str>>

Returns an iterator over all variants in this enum.

impl Serialize for Phrase

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

where __S: Serializer,

Serialize this value into the given Serde serializer.