Like many others here I once wrote a toy lisp in golang, and I added a help function. It would give usage-information for all the built-in functions.
> (help +)
Arguments N arg1..argN
Adds all arguments present to the first number.
> (help map)
Arguments lst:list fun:function
Return a list with the contents of evaluating the given function on every item of the supplied list.
See-also: map-pairs
