Struct Condition 

pub struct Condition { /* private fields */ }

Public query types: a Condition groups into a Conjunction, conjunctions into a DnfQuery. Represents a single field operator value test in a DNF query.

Conditions are the leaves of a query: a Conjunction is an AND of conditions, and a DnfQuery is an OR of conjunctions.

Examples

use dnf::{DnfQuery, Op};

let query = DnfQuery::builder()
    .or(|c| c.and("age", Op::GT, 18))
    .build();

let condition = &query.conjunctions()[0].conditions()[0];
assert_eq!(condition.field_name(), "age");
assert_eq!(condition.operator(), &Op::GT);

Implementations

impl Condition

pub fn field_name(&self) -> &str

Returns the field name this condition tests.

pub fn operator(&self) -> &Op

Returns the operator used by this condition.

pub fn value(&self) -> &Value

Returns the right-hand value this condition compares against.

pub fn evaluate<T: DnfEvaluable>(&self, target: &T) -> bool

Evaluates the condition against a single target.

Returns whatever DnfEvaluable::evaluate_field returns. Custom operators are not dispatched here — call DnfQuery::evaluate for that.

Examples

use dnf::{Condition, DnfEvaluable, Op, Value};

#[derive(DnfEvaluable)]
struct User { age: u32 }

let user = User { age: 30 };
let cond = dnf::DnfQuery::builder()
    .or(|c| c.and("age", Op::GT, 18))
    .build()
    .conjunctions()[0]
    .conditions()[0]
    .clone();
assert!(cond.evaluate(&user));

Trait Implementations

impl Clone for Condition

fn clone(&self) -> Condition

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Condition

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Condition

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Condition

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

Formats the value using the given formatter.

impl PartialEq for Condition

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for Condition

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 Condition