unless ViewHelper `<vhs:unless>`

Unless

The opposite of f:if and only supporting negative matching. Related to v:or but allows more complex conditions.

Is the same as writing:

<f:if condition="{theThingToCheck}">
    <f:else>
        The thing that gets done
    </f:else>
</f:if>

Except without the f:else.

Example, tag mode

<v:unless condition="{somethingRequired}">
    Warning! Something required was not present.
</v:unless>

Example, inline mode illustrating `v:or` likeness

{defaultText -> v:unless(condition: originalText)}
    // which is much the same as...
{originalText -> v:or(alternative: defaultText}
    // ...but the "unless" counterpart supports anything as
    // condition instead of only checking "is content empty?"

Arguments

then

DataType: mixed
Required: false
Description: Value to be returned if the condition if met.

else

DataType: mixed
Required: false
Description: Value to be returned if the condition if not met.

condition

DataType: boolean
Required: true
Description: Condition which must be true, or then is rendered