Block helpers in Mutate blocks

Hi there,
can we use block helpers inside mutate blocks?
I am getting an invalid template error for such simple block:

You can use block helpers, but that format is not a valid {{#if}} helper. Instead, try …

{{#eq working.device.test null}}test is missing{{/eq}}

Interesting, when and where should I use the if block?
For example I want to use that in combination with a regex condition.

I think the Handlebars documentation explains it best.

As for matching on a regular expression, Losant has a custom block helper for that. From our documentation:

{{#match str regExpStr}}: Returns true if str matches the regular expression regExpStr.

Gosh I feel dumb, apparently you can also do:

{{#if (eq person "John")}} hello {{/if}}

I guess #eq is the shortened version of the #if (eq ) syntax.

Did you really get that to work? If so, where did you apply it? I wold not expect that syntax to work when trying to use a block helper as a subexpression.

This is a new world to me, apparently that syntax is only available with this:

which I discovered to be not the vanilla Handlebar solution!
Love the payload tester, useful!