SelectExpression

public protocol SelectExpression

A protocol which represents a select expression. A select expression can be applied to a Row to produce a value. This is typically used to filter Relations using expressions which return booleans.

  • constantBoolValue Extension method

    If the SelectExpression is a SelectExpressionConstantValue, returns its boolean value. Otherwise returns nil.

    Declaration

    Swift

    public var constantBoolValue: Bool? { get }
  • binaryOperands(_:) Extension method

    If the expression is a SelectExpressionBinaryOperator and the operator is an instance of the given type, then return the two operands. Otherwise return nil.

    Declaration

    Swift

    func binaryOperands<T>(_ op: T.Type) -> (SelectExpression, SelectExpression)? where T : BinaryOperator