Arithmetic Operators | Description | Example |
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Arithmetic operators operators behave the same as
Note |
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All arithmetic operators return a floating point number. If an integer is desired, then the global function {{parseInt}} should be used to cast the arithmetic expression as an integer. |
Example:
1/2 = .5
parseInt(1/2) = 0
In this section
Child pages (Children Display) |
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Logical Operators
Logical operators (&&, ||, !) behave the same as JavaScript logical operators.
String Operators
String operators (+) behave the same as JavaScript string operators except that the shorthand assignment operator (+=) is not supported.
Spread Operators
The spread operator (...) Spread Operator | Description | Examples |
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(...) | This operator makes it easier to build arrays, objects, and call functions where the list of arguments is built at runtime. For instance, while using in an array literal, the value on the right of the operator is inserted into the new array at that position. Similarly, in a function call, the array expands and is used as the arguments to the function. In an object literal, the right side of the operator is another object that has its keys added to the new object. |
Examples:
To build a new array that is made up of another array surrounded by two elements: Code Block |
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["header", ...$body, "footer"] |
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If you want to To find the maximum value in an array of numbers: Code Block |
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Math.max(...$numbers) |
To create a new object with some fixed values and entries in the "$extra" object: Code Block |
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{ first_name: $fname, last_name: $lname, ... $extra } |
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OperatorsinfoiconfalseExample |
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Conditional (Ternary) |
The conditional operator (?) | This operator allows you to specify a value to use based on the result of an expression. |
The syntax is as follows: Code Block |
condition ? trueValue : falseValue The condition expression will be evaluated and the trueValue will be the result of the expression if the condition evaluates to true, |
otherwise else the falseValue will be the result. |
Examplecondition ? trueValue : falseValue |
Code Block |
Example: Code Block |
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icon | false
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instanceof | The instanceof operator returns True if the given object is an instance of the given type. |
The syntax is as follows: Code Block |
type | $my_array instanceof Array |
The possible values for the type are: Null, Boolean, String, Number, Object, Array, Date, LocalDate, DateTime, and LocalDateTime. |
Example:
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$my_array instanceof Array
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The match
This operator allows you to conditionally evaluate one of a number of expressions based on whether an input value matches a given pattern. See the match Control Flow Operator |
section Example:
Code Block |
Info |
iconfalse | typeof | The typeof operator returns the type of a value as a string. |
The syntax is as follows:typeof
operand
The possible return values are: "boolean", "number", "string", "object", and "array". | typeof operand |
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in | The in operator returns true if the property name or array index is in the given object or array. |
The syntax is as follows: Info |
iconfalse | Example:
You can add notes to your expressions using comments. A comment starts with '/*' and ends with '*/', for example:
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/* say hello */ "Hello, World!"
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The comment will be is ignored when evaluating the expression, it expression—it is only for the reader's benefit.
Operator Precedence
Operator Type | Individual Operators |
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member | . [] |
call | () |
negation | ! - |
multiply/divide | * / % |
addition/subtraction | + - |
relational | < <= > >= |
equality | == != |
logical-and | && |
logical-or | || |
comma | , |
Unsupported Operations
- Assignment
- Creating variables and assigning values is not supported
- Example: var temp = 10
- Short hand assignment
- Strict equals
- Strict not equals
- Increment
- Decrement
Accessing Document Values
To access values in a document, you can use JavaScript object accessors can be used.
For a given document data:
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{ first_name: "James", last_name: "Smith" } The expression $first_name would return the 'first_name' property which is James. |
The You can also access the 'first_name' property |
can also be accessed by using array notation $['first_name']. JavaScript array accessors can be used also if the object is an array/list. For a given document data: [ 1, 2, 3]
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$[1] would return the value 2. |
More complex exampleComplex Example:
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{ names: ["Joe", "Bob", "Fred"] } $names[2] would return the value Fred. |
Arrow Functions
Custom You can create custom expression language functions can be created using the arrow function syntax:
Code Block |
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// A function that takes multiple parameters:
(param1, param2, ..., paramN) => expression
// A function that takes a single parameter does not need parentheses:
(param) => expression
param => expression
// A function with no parameters requires parentheses:
() => expression
// Function parameters can also have default values
(param1 = defaultValue1, param2 = defaultValue2, ..., paramN = defaultValueN) => expression |
These functions can be passed to other functions that accept callbacks, like Array.map() or Array.filter(), or they can be put into an expression library for use in any expression property in your pipelinesPipelines.
Example
To multiply all numbers in an array by ten:
[1, 2, 3].map(x => x * 10)
Result:
[10, 20, 30]