Enum Predicate 

pub enum Predicate {
    Comparison {
        left: Box<Expr>,
        operator: ComparisonOperator,
        right: Box<Expr>,
    },
    IsNull(Box<Expr>),
    And(Box<Predicate>, Box<Predicate>),
    Or(Box<Predicate>, Box<Predicate>),
    Not(Box<Predicate>),
    True,
    False,
    Placeholder,
}

Variants

Comparison

Fields

left: Box<Expr>

operator: ComparisonOperator

right: Box<Expr>

IsNull(Box<Expr>)

And(Box<Predicate>, Box<Predicate>)

Or(Box<Predicate>, Box<Predicate>)

Not(Box<Predicate>)

True

False

Placeholder

Implementations

impl Predicate

pub fn walk<T, F>(&self, accumulator: T, visitor: &mut F) -> T

where F: FnMut(T, &Predicate) -> T,

Recursively walk a predicate tree and accumulate results using a closure

pub fn assume_null(&self, columns: &[String]) -> Self

Clones the predicate tree and evaluates comparisons involving missing columns as if they were NULL

pub fn populate<I, V, E>(self, values: I) -> Result<Predicate, ParseError>

where I: IntoIterator<Item = V>, V: TryInto<Expr, Error = E>, E: Into<ParseError>,

Populate placeholders in the predicate with actual values

Trait Implementations

impl Clone for Predicate

fn clone(&self) -> Predicate

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Predicate

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Predicate

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Predicate

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

Formats the value using the given formatter.

impl From<Predicate> for Selection

fn from(predicate: Predicate) -> Self

Converts to this type from the input type.

impl PartialEq for Predicate

fn eq(&self, other: &Predicate) -> 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 Serialize for Predicate

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl<'a> TryFrom<&'a str> for Predicate

type Error = ParseError

The type returned in the event of a conversion error.

fn try_from(value: &'a str) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Expr> for Predicate

type Error = ParseError

The type returned in the event of a conversion error.

fn try_from(value: Expr) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<String> for Predicate

type Error = ParseError

The type returned in the event of a conversion error.

fn try_from(value: String) -> Result<Self, Self::Error>

Performs the conversion.

impl StructuralPartialEq for Predicate