'short-forming' functions =)

Script Newbie question:

I like 'short-forms' and at the moment I try to create some for my keyboard checks. This is the basic idea:

keyPress= function(key, todo)
  if keyboard.press[key] then todo() end
end

update = function()
  keyPress("SPACE", function() x+=1 end)  // works
end

That works as shown, but since I'm a lazy guy I would like to replace the function call with this:

keyPress("SPACE", "x+=1")

Is there any (easy) way to do that?

Live Long And Tinker

P.S. this is a double up of a question I posted on the discord channel, but I thought it might be of general interest

That actually works? I had no idea, that sounds pretty useful! (especially since I am lazy as well)

Update:

I took the liberty to forward @gilles reply from the discord channel:

This would require to have some sort of eval function, which microScript doesn't have. Your working way looks very fine to me.
Not really shorter, but I would probably like to do it this way:

bindings = object end  // just create an empty object
bindings.SPACE = function() x += 1 end
bindings.UP = function() y += 1 end 
(...) // more bindings
update = function()
  for b in bindings
    if keyboard.press[b] then bindings[b]() end
  end
end

(Note: for ... in when applied to an object, iterates over the object's defined properties)