Is Empty#

The Is Empty converter inspects the input value and reports whether it qualifies as empty. The Result Type setting controls whether the converter outputs a boolean flag or passes the input value through. The converter treats a value as empty when it is one of the following:

A string that is blank, whitespace-only, {}, or [].
An array with no items.
An object with no properties.
An object whose only property is $id.

The converter reports all other values as not empty, including numbers, booleans, dates, null, and undefined.

Settings#

Name	Data Type	Possible Values	Description
resultType	`Enum`	`Boolean` `NullOrValue`	Controls the output. `Boolean` returns `true` when the input is empty and `false` otherwise. `NullOrValue` returns `undefined` when the input is empty and passes the input value through otherwise. Default is `Boolean`.

Table 1: Settings

Examples#

Boolean Result#

Input	Output
`""`	`true`
`" "`	`true`
`"{}"`	`true`
`"[]"`	`true`
`"hello"`	`false`
`[]`	`true`
`[1, 2, 3]`	`false`
`{}`	`true`
`{ "$id": "123" }`	`true`
`{ "$id": "123", "name": "x" }`	`false`
A Date value	`false`
`null`	`false`
`42`	`false`

Table 2: Examples with the Boolean result type

NullOrValue Result#

Input	Output
`""`	`undefined`
`"{}"`	`undefined`
`"[]"`	`undefined`
`[]`	`undefined`
`["a"]`	`["a"]`
`"hello"`	`"hello"`

Table 3: Examples with the NullOrValue result type

Failure Behavior#

This converter never fails. See Converters for the full set of failure patterns across converters.