I am creating a book that presents readers with a list of recommended materials.

If materials are listed, then its displayed under the \subject{Materials} heading in a simple itemized list.

I'm using \doifsomething{} to check if any items are listed.

The problem I'm having is, when fed a blank macro, `\define\needsoven{}` it thinks there is content, so it displays the "Materials" heading, but an empty list. I have a custom macro that determins "if oven is needed" independent of these other items. So I need `\define\needsoven{}` to be regarded as nothing.

How can I get \doifsomething{} to think \define\needsoven{} is an empty value?


My minimal working example is below:




    \chapter{Recipe 1}
            Spread peanut butter on sandwich.
    \chapter{Recipe 2}
        \materialsneeded{\item pizza cutter \item stove}
            Preheat oven to 450 degrees F.