expr

package

v1.21.0 Latest Latest Go to latest Published: Mar 13, 2026 License: MIT Imports: 5 Imported by: 0

Details

Package expr provides a predicate expression parser and evaluator for the oq query language.

This section is empty.

This section is empty.

This section is empty.

type Expr interface {
	Eval(row Row) Value
}

Expr is the interface for all expression nodes.

func Parse(input string) (Expr, error)

Parse parses a predicate expression string into an Expr tree.

type Row interface {
	Field(name string) Value
}

Row provides field access for predicate evaluation.

type Value struct {
	Kind ValueKind
	Str  string
	Int  int
	Bool bool
}

Value represents a typed value in the expression system.

func BoolVal(b bool) Value

BoolVal creates a bool Value.

func IntVal(n int) Value

IntVal creates an int Value.

func NullVal() Value

NullVal creates a null Value.

func StringVal(s string) Value

StringVal creates a string Value.

type ValueKind int

const (
	KindString ValueKind = iota
	KindInt
	KindBool
	KindNull
)