A specialized predicate that you use to compare expressions.


You use comparison predicates to compare the results of two expressions. You create a comparison predicate with an operator, a left expression, and a right expression. You represent the expressions using instances of the NSExpression class. When you evaluate the predicate, it returns as a BOOL value the result of invoking the operator with the results of evaluating the expressions.


Creating Comparison Predicates

init(leftExpression: NSExpression, rightExpression: NSExpression, customSelector: Selector)

Initializes a predicate formed by combining given left and right expressions using a given selector.

init(leftExpression: NSExpression, rightExpression: NSExpression, modifier: NSComparisonPredicate.Modifier, type: NSComparisonPredicate.Operator, options: NSComparisonPredicate.Options = [])

Initializes a predicate to a given type formed by combining given left and right expressions using a given modifier and options.

Getting Information About a Comparison Predicate

var comparisonPredicateModifier: NSComparisonPredicate.Modifier

The comparison predicate modifier for the receiver.

var customSelector: Selector?

The selector for the receiver.

var rightExpression: NSExpression

The right expression for the receiver.

var leftExpression: NSExpression

The left expression for the receiver.

var options: NSComparisonPredicate.Options

The options that are set for the receiver.


enum NSComparisonPredicate.Modifier

These constants describe the possible types of modifier for NSComparisonPredicate.

struct NSComparisonPredicate.Options

These constants describe the possible types of string comparison for NSComparisonPredicate. These options are supported for LIKE as well as all of the equality/comparison operators.

enum NSComparisonPredicate.Operator

Defines the type of comparison for NSComparisonPredicate.


Inherits From

Conforms To

See Also


class NSPredicate

A definition of logical conditions used to constrain a search either for a fetch or for in-memory filtering.

class NSExpression

An expression for use in a comparison predicate.

class NSCompoundPredicate

A specialized predicate that evaluates logical combinations of other predicates.