Enum Expr 

pub enum Expr {
    And(Box<Expr>, Box<Expr>),
    Or(Box<Expr>, Box<Expr>),
    Not(Box<Expr>),
    Cmp {
        lhs: Operand,
        op: CmpOp,
        rhs: Operand,
    },
    Between {
        field: Operand,
        low: Operand,
        high: Operand,
        negated: bool,
    },
}

A filter expression. A recursive tree, produced by crate::parse.

Variants

And(Box<Expr>, Box<Expr>)

Combined AND expression.

Or(Box<Expr>, Box<Expr>)

Kombinierter OR-Ausdruck.

Not(Box<Expr>)

NOT-Negation.

Cmp

Comparison between two operands.

Fields

lhs: Operand

Linker Operand.

op: CmpOp

Operator.

rhs: Operand

Rechter Operand.

Between

field BETWEEN low AND high (spec §B.2.1 BetweenPredicate). Equivalent to field >= low AND field <= high. negated = true for NOT BETWEEN.

Fields

field: Operand

Field operand (left of BETWEEN).

low: Operand

Lower bound (inclusive).

high: Operand

Upper bound (inclusive).

negated: bool

NOT BETWEEN?

Implementations

impl Expr

pub fn node_count(&self) -> usize

Recursive sub-expression count (useful for tests / metrics).

pub fn collect_param_indices(&self) -> Vec<u32>

Collects all parameter indices that occur in the expression.

impl Expr

pub fn evaluate<R: RowAccess>( &self, row: &R, params: &[Value], ) -> Result<bool, EvalError>

Evaluates the expression against a row + parameter slice.

Errors

Siehe EvalError.

Trait Implementations

impl Clone for Expr

fn clone(&self) -> Expr

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Expr

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

Formats the value using the given formatter.

impl PartialEq for Expr

fn eq(&self, other: &Expr) -> 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 StructuralPartialEq for Expr