none() Function

Function

none( predicate, list, context )

Calls a rule or function that returns either true or false for each item in list by asking the question, "Do all items in this list yield false for this rule/function?" with the intent to discover if no items will yield true.

Parameters

Keyword Type Description

predicate

Function, Rule, or Data Type Constructor

Expression that returns a Boolean (true or false).

list

Any Type Array

List of elements that the predicate iterates through.

context

Any Type Array

Variable number of parameters passed directly into each predicate evaluation.

Returns

Boolean

Usage considerations

Referencing expressions and rules

Use fn!functionName to reference an expression function and rule!ruleName to reference a rule.

Understanding results

Returns false as soon as the returned value of an evaluation yields true; otherwise, returns true.

Empty and null lists yield true.

Limitations and alternatives

Serves as an alternative to not(or(apply(rule!iseven, {1, 2, 3}))) and not(any(rule!iseven, {-1,0,1,2})).

a!forEach() cannot be used within rules used in this function.

Examples

Given a function f(x), none(fn!f, {a, b, c}, v) returns not(or({f(a, v), f(b, v), f(c, v)}))

none(rule!iseven,{-1,0,1,2}) returns false

Feature compatibility

The table below lists this function's compatibility with various features in Appian.
Feature Compatibility Note
Portals Compatible
Offline Mobile Compatible
Custom Record Field Expressions Compatible
Process Reports Incompatible

You cannot use this function to configure a process report.

Process Events Incompatible

You cannot use this function to configure a process event node, such as a start event or timer event.

Open in Github Built: Fri, Sep 23, 2022 (01:20:36 PM)

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