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ComparisonValueOperators

Operators to compare two values.

To learn more about aggregation operators, view AggregationOperators.

Inheritors

Properties

context

@LowLevelApi



abstract override val context: BsonContext

The strategy used when converting from KProperty1 to Field.

field

Converts a Kotlin property into a Field.

Functions

div

open operator fun <Context : Any, Root, Child> Value<Context, Root>.div(field: Field<Root, Child>): Value<Context, Child>

Refers to field as a nested field of the current value.

Examples
class User(
    val name: String,
)

class Data(
    val users: List<User>,
    val userNames: List<Int>,
)

data.aggregate()
    .set {
        Data::userNames set Data::users.map { it / User::name }
    }
External resources
open operator fun <Context : Any, Root, Child> Value<Context, Root>.div(field: KProperty1<Root, Child>): Value<Context, Child>

Refers to field as a nested field of the current value.

Examples
class User(
    val name: String,
)

class Data(
    val users: List<User>,
    val userNames: List<Int>,
)

data.aggregate()
    .set {
        Data::userNames set Data::users.map { it / User::name }
    }
External resources

eq

open infix fun <Context : Any, Result> Value<Context, Result>.eq(other: Value<Context, Result>): Value<Context, Boolean>

Compares two aggregation values and returns true if they are equivalent.

Example
class Product(
    val name: String,
    val creationDate: Instant,
    val releaseDate: Instant,
)

val releasedOnCreation = collection.aggregate()
    .match {
        expr {
            of(Product::creationDate) eq of(Product::releaseDate)
        }
    }
    .toList()
External resources

See also

get

open operator fun <Root, Type> KProperty1<Root, Collection<Type>>.get(index: Int): Field<Root, Type>

Refers to a specific item in an array, by its index.

open operator fun <Root, Type> KProperty1<Root, Map<String, Type>>.get(index: String): Field<Root, Type>

Refers to a specific item in a map, by its name.

open operator fun <Root, Type> Field<Root, Collection<Type>>.get(index: Int): Field<Root, Type>

Refers to a specific item in an array, by its index.

open operator fun <Root, Type> Field<Root, Map<String, Type>>.get(key: String): Field<Root, Type>

Refers to a specific item in a map, by its name.

gt

open infix fun <Context : Any, Result> Value<Context, Result>.gt(other: Value<Context, Result>): Value<Context, Boolean>

gte

lt

open infix fun <Context : Any, Result> Value<Context, Result>.lt(other: Value<Context, Result>): Value<Context, Boolean>

lte

ne

open infix fun <Context : Any, Result> Value<Context, Result>.ne(other: Value<Context, Result>): Value<Context, Boolean>

Compares two aggregation values and returns true if they are not equivalent.

Example
class Product(
    val name: String,
    val creationDate: Instant,
    val releaseDate: Instant,
)

val notReleasedOnCreation = collection.aggregate()
    .match {
        expr {
            of(Product::creationDate) eq of(Product::releaseDate)
        }
    }
    .toList()
External resources

See also

of

open fun <Context : Any, Result> of(field: Field<Context, Result>): Value<Context, Result>

Refers to a field within an aggregation value.

Example
class Product(
    val acceptanceDate: Instant,
    val publishingDate: Instant,
)

val publishedBeforeAcceptance = products.find {
    expr {
        of(Product::publishingDate) lt of(Product::acceptanceDate)
    }
}

Refers to a field within an aggregation value.

Example
class Product(
    val acceptanceDate: Instant,
    val publishingDate: Instant,
)

val publishedBeforeAcceptance = products.find {
    expr {
        of(Product::publishingDate) lt of(Product::acceptanceDate)
    }
}
open fun <Result> of(value: Result): Value<Any, Result>

Refers to a Kotlin value within an aggregation value.

Example
class Product(
    val age: Int,
)

val publishedBeforeAcceptance = products.find {
    expr {
        of(Product::age) lt of(15)
    }
}
open fun of(value: BsonType): Value<Any, BsonType>

Refers to a BsonType within an aggregation value.

Example
class Product(
    val age: Int,
)

val publishedBeforeAcceptance = products.find {
    expr {
        of(Product::age).type eq of(BsonType.Int32)
    }
}

unsafe

open infix fun <Root, Child> KProperty1<Root, *>.unsafe(child: String): Field<Root, Child>

Refers to a field child of the current field, with no compile-time safety.

open infix fun <Root, Child> KProperty1<Root, *>.unsafe(child: KProperty1<*, Child>): Field<Root, Child>

Refers to a field child of the current field, without checking that it is a field available on the current object.

open infix fun <Root, Child> KProperty1<Root, *>.unsafe(child: Field<*, Child>): Field<Root, Child>

Refers to a field child of the current field, without checking that it is a field available on the current object.

open infix fun <Root, Child> Field<Root, *>.unsafe(child: KProperty1<*, Child>): Field<Root, Child>

Refers to a field child of the current field, without checking that it is a field available on the current object.

open infix fun <Root, Child> Field<Root, *>.unsafe(child: Field<*, Child>): Field<Root, Child>

Refers to a field child of the current field, without checking that it is a field available on the current object.

open infix fun <Root, Type, Child> Field<Root, Type>.unsafe(child: String): Field<Root, Child>

Refers to a field child of the current field, with no compile-time safety.