I think the good rule of thumb is to have longer names in bigger scopes. So a variable for short loop or an argument to 1 line function can be single char, whil

I think the good rule of thumb is to have longer names in bigger scopes. So a variable for short loop or an argument to 1 line function can be single char, while arguments to medium length functions are a word, and globals (including functions) are one or multiple words. To get to your example, the preferred signature would be: square:{x*x}