Trollies are usually plastic-coated. If you're gonna do this please burn it off first with a nice hot fire, then scrub off all the plastic residue before cooking food on it.

If it's tin- or zinc-plated you run the risk of metal fume fever if you breathe the fumes, but once-off it's probably not much of a hazard. Unless it's cadmium plated (peculiar yellowish hue), in which case the fumes and residue are quite hazardous.

It's also worth bringing a spanner to remove the castors – they're usually decent quality and can be used for better purposes than a shopping trolley.

Not sure if any of this advice transfers with the programming analogy.