Query Expressions¶

Description¶

We provide a system for filtering state queries via expressions similar to those used by mongoDB.

Data Structures¶

Expression¶

interface Expression {
  [operator: string]: Array<string | number | Expression>
}

Description¶

Represents an expression. All expressions consist of an operator and a list of input values. Some expressions take other operators as input values.

Operators¶

Boolean Operators¶

$and¶

{ $and: [ <expression1>, <expression2>, ... ] }

Description¶

Returns true if all arguments evaluate to true.

Parameters¶

expressions - Expression[]: Any number of Expression objects.

Returns¶

boolean: true if all arguments resolve to true, false otherwise.

$not¶

{ $not: [ <expression> ] }

Description¶

Returns the boolean opposite of the result of the argument expression.

Parameters¶

expression: Expression: A single Expression object.

Returns¶

boolean: true if the expression resolves to false, false otherwise.

$or¶

{ $or: [ <expression1>, <expression2>, ... ] }

Description¶

Returns true if any argument evaluates to true.

Parameters¶

expressions - Expression[]: Any number of Expression objects.

Returns¶

boolean: true if any argument resolves to true, false otherwise.

Comparison Operators¶

$eq¶

{ $eq: [ <argument1>, <argument2>, ... ] }

Description¶

Checks if all arguments are equal.

Parameters¶

arguments - any[]: List of input values.

Returns¶

boolean: true if all arguments are equal, false otherwise.

$gt¶

{ $gt: [ <argument1>, <argument2> ] }

Description¶

Checks if the first argument is greater than the second.

Parameters¶

argument1 - any: First input value.
argument2 - any: Second input value.

Returns¶

boolean: true if the first argument is greater than the second, false otherwise.

$gte¶

{ $gte: [ <argument1>, <argument2> ] }

Description¶

Checks if the first value is greater than or equal to the second.

Parameters¶

argument1 - any: First input value.
argument2 - any: Second input value.

Returns¶

boolean: true if the first value is greater than or equal to the second, false otherwise.

$lt¶

{ $lt: [ <argument1>, <argument2> ] }

Description¶

Checks if the first value is less than the second.

Parameters¶

argument1 - any: First input value.
argument2 - any: Second input value.

Returns¶

boolean: true if the first value is less than the second, false otherwise.

$lte¶

{ $lte: [ <argument1>, <argument2> ] }

Description¶

Checks if the first value is less than or equal to the second.

Parameters¶

argument1 - any: First input value.
argument2 - any: Second input value.

Returns¶

boolean: true if the first value is less than or equal to the second, false otherwise.

$ne¶

{ $ne: [ <argument1>, <argument2>, ... ] }

Description¶

Returns true if input values are not all equivalent.

Parameters¶

arguments - any[]: List of input values.

Returns¶

boolean: true if input values are not equivalent, false otherwise.