Operators

Just as a sentence means nothing without a verb, anything you write in RuLa means nothing without operators. They make it possible for a variable to be defined, for a condition to work and for a rule to make sense.
The table below lists all available operators in alphabetical order, with a brief description. For a more extensive description of each individual operator, plus examples, click on it or visit the sub-pages in the menu on the left.
Available Operators and Keywords
Operator
Category
Description
​=​
​Boolean​
Compares. Evaluates to either true or false, delivering different outcomes.
​!=​
​Boolean​
Compares, true for 'is not equal to'.
​>​
​Boolean​
Compares, true for 'greater than'.
​>=​
​Boolean​
Compares, true for 'equal to or greater than'.
​<​
​Boolean​
Compares, true for 'less than'.
​<=​
​Boolean​
Compares, true for 'equal to or less than'.
​:=​
​Special​
Assignment, which can have any kind of expression on the right side of the operator.
​+, -, /, *, %​
​Mathematical​
Perform basic mathematical calculations.
​[ , ]​
​List​
Creates a new list from single values, allowing other list operators to perform actions on the new list.
​ADD_YEARS​
​Date​
Takes a date and adds a specified number of years to it.
​AFTER​
​Date​
Takes two dates, and checks if the first one comes after the second one.
​AFTER_EQUAL​
​Date​
Takes two dates, and checks if the first one comes after, or is the same as, the second one.
​ALL​
​List​
Evaluates if all values in a list are true.
​and​
​Boolean​
Sets as condition that both expressions have to be true to have the entire expression evaluate to 'true'.
​and then​
​Boolean​
Similar as above, but when using 'and then', the second question is only asked when the first evaluates to 'true'.
​AVG​
​Mathematical​
Calculates the average value.
​AVG_OF_ANY​
​Known​
Calculates the average of available values.
​BEFORE​
​Date​
Takes two dates, and checks if the first one comes before the second one.
​BEFORE_EQUAL​
​Date​
Takes two dates, and checks if the first one comes before, or is the same as, the second one.
​calculated_name​
​String​
Accesses the calculated name of an instance.
​CEIL​
​Mathematical​
Returns the value of the given parameter, rounded up to a whole number.
​CONCAT​
​String​
Combines two values into one new value, specifying what should separate the two.
​contains​
​List​
Goes over a list, which is given on the left of the operator. Evaluates to 'true' if the single value on the right is present in the given list.
​contains all​
​List​
Expressions with this operator will only evaluate to 'true' if all values from the list on the right side are present in the list on the left side.
​contains any​
​List​
Going over a list, given on the left side of the operator, this operator has the expression evaluate to true if any value from that list is present in a list or the single value given on the right side.
​COUNT​
​List​
Returns the number of occurrences of the given parameter.
​ensure​
​Special​
Makes sure a case contains at least, for example, 1 Person. (replaces create)
​FIRST_ELEMENT​
​List​
Returns the first element from a list.
​FLOOR​
​Mathematical​
Returns the value of the given parameter, rounded down to a whole number.
​get_attr​
​Special​
Gives access to named properties of an instance using expressions.
​get_properties​
​Special​
Returns specific information on an instance's properties.
​in​
​List​
Checks if  a value is present in a taxonomy.
​instances​
​Special​
Returns all instances of the given type(s) living on the platform.
​is​
​Special​
Basic assignment of a variable.
​JOIN​
​String​
Combines a list of values into one new value by appending them.
​known​
​Known​
Sets a condition for when a property is not unknown.
​LIST_OF_ANY​
​Known​
Builds a list of only the values that are available out of all the values it is given.
​MAP​
​List​
Performs the same action on each individual value in a list.
​MAX​
​Mathematical​
Returns the highest value.
​MAX_OF_ANY​
​Known​
Returns the highest out of available values.
​MIN​
​Mathematical​
Returns the lowest value.
​MIN_OF_ANY​
​Known​
Returns the lowest out of available values.
​not​
​Boolean​
A negation.
​not in​
​List​
Evaluates to true if the given value is absent from the specified taxonomy.
​NOW​
​Date​
Current date and time.
​ontology​
​Special​
Sets a condition based on the type of ontology.
​optional​
​Special​
The rule can accept, but will not require, for example, a third person.
​or​
​Boolean​
When just one of the two given expressions is true, the entire expression evaluates to 'true'.
​or else​
​Boolean​
Similar to above, but the second question is only asked if the first has been answered.
​roles​
​Special​
Sets a condition based on role(s).
​ROUND​
​Mathematical​
Returns the value of the given parameter, rounded to a whole number.
​self​
​Special​
Refers to the current instance where you use it.
​SNEAKY​
​Known​
Wrapping an expression with SNEAKYhas the system ignore the expression, if the information used in it is not available.
​SOME​
​List​
Evaluates if any value in a list is true.
​SUBTRACT_YEARS​
​Date​
Takes a date and subtracts a specified number of years to it.
​SUM​
​Mathematical​
Adds up numbers.
​SUM_OF_ANY​
​Known​
Adds available numbers.
​SUM_PRODUCT​
​Mathematical​
Multiplies values in one list with values on the same index in another list. Returns the sum of the multiplications.
​UNION​
​List​
Combines the elements of two sets into one single set.
​UNION_OF_ANY​
​Known​
Creates a combined list of the available values and lists out of all values and lists you provide.
​unknown​
​Known​
Sets a condition for when a property is unknown.
​YEARS_AGO​
​Date​
Calculates the number of years since a given date.

Last modified 2yr ago

Operator	Category	Description
`=`	Boolean	Compares. Evaluates to either true or false, delivering different outcomes.
`!=`	Boolean	Compares, true for 'is not equal to'.
`>`	Boolean	Compares, true for 'greater than'.
`>=`	Boolean	Compares, true for 'equal to or greater than'.
`<`	Boolean	Compares, true for 'less than'.
`<=`	Boolean	Compares, true for 'equal to or less than'.
`:=`	Special	Assignment, which can have any kind of expression on the right side of the operator.
`+`, `-`, `/`, `*`, `%`	Mathematical	Perform basic mathematical calculations.
`[ , ]`	List	Creates a new list from single values, allowing other list operators to perform actions on the new list.
`ADD_YEARS`	Date	Takes a date and adds a specified number of years to it.
`AFTER`	Date	Takes two dates, and checks if the first one comes after the second one.
`AFTER_EQUAL`	Date	Takes two dates, and checks if the first one comes after, or is the same as, the second one.
`ALL`	List	Evaluates if all values in a list are true.
`and`	Boolean	Sets as condition that both expressions have to be true to have the entire expression evaluate to 'true'.
`and then`	Boolean	Similar as above, but when using 'and then', the second question is only asked when the first evaluates to 'true'.
`AVG`	Mathematical	Calculates the average value.
`AVG_OF_ANY`	Known	Calculates the average of available values.
`BEFORE`	Date	Takes two dates, and checks if the first one comes before the second one.
`BEFORE_EQUAL`	Date	Takes two dates, and checks if the first one comes before, or is the same as, the second one.
`calculated_name`	String	Accesses the calculated name of an instance.
`CEIL`	Mathematical	Returns the value of the given parameter, rounded up to a whole number.
`CONCAT`	String	Combines two values into one new value, specifying what should separate the two.
`contains`	List	Goes over a list, which is given on the left of the operator. Evaluates to 'true' if the single value on the right is present in the given list.
`contains all`	List	Expressions with this operator will only evaluate to 'true' if all values from the list on the right side are present in the list on the left side.
`contains any`	List	Going over a list, given on the left side of the operator, this operator has the expression evaluate to true if any value from that list is present in a list or the single value given on the right side.
`COUNT`	List	Returns the number of occurrences of the given parameter.
`ensure`	Special	Makes sure a case contains at least, for example, 1 Person. (replaces `create`)
`FIRST_ELEMENT`	List	Returns the first element from a list.
`FLOOR`	Mathematical	Returns the value of the given parameter, rounded down to a whole number.
`get_attr`	Special	Gives access to named properties of an instance using expressions.
`get_properties`	Special	Returns specific information on an instance's properties.
`in`	List	Checks if a value is present in a taxonomy.
`instances`	Special	Returns all instances of the given type(s) living on the platform.
`is`	Special	Basic assignment of a variable.
`JOIN`	String	Combines a list of values into one new value by appending them.
`known`	Known	Sets a condition for when a property is not unknown.
`LIST_OF_ANY`	Known	Builds a list of only the values that are available out of all the values it is given.
`MAP`	List	Performs the same action on each individual value in a list.
`MAX`	Mathematical	Returns the highest value.
`MAX_OF_ANY`	Known	Returns the highest out of available values.
`MIN`	Mathematical	Returns the lowest value.
`MIN_OF_ANY`	Known	Returns the lowest out of available values.
`not`	Boolean	A negation.
`not in`	List	Evaluates to true if the given value is absent from the specified taxonomy.
`NOW`	Date	Current date and time.
`ontology`	Special	Sets a condition based on the type of ontology.
`optional`	Special	The rule can accept, but will not require, for example, a third person.
`or`	Boolean	When just one of the two given expressions is true, the entire expression evaluates to 'true'.
`or else`	Boolean	Similar to above, but the second question is only asked if the first has been answered.
`roles`	Special	Sets a condition based on role(s).
`ROUND`	Mathematical	Returns the value of the given parameter, rounded to a whole number.
`self`	Special	Refers to the current instance where you use it.
`SNEAKY`	Known	Wrapping an expression with `SNEAKY`has the system ignore the expression, if the information used in it is not available.
`SOME`	List	Evaluates if any value in a list is true.
`SUBTRACT_YEARS`	Date	Takes a date and subtracts a specified number of years to it.
`SUM`	Mathematical	Adds up numbers.
`SUM_OF_ANY`	Known	Adds available numbers.
`SUM_PRODUCT`	Mathematical	Multiplies values in one list with values on the same index in another list. Returns the sum of the multiplications.
`UNION`	List	Combines the elements of two sets into one single set.
`UNION_OF_ANY`	Known	Creates a combined list of the available values and lists out of all values and lists you provide.
`unknown`	Known	Sets a condition for when a property is unknown.
`YEARS_AGO`	Date	Calculates the number of years since a given date.