Re: Shift selection using interactive spec

[Richard Stallman]

    Then the second arg to `interactive' could be just a lambda
    with one argument with the value this function returns, e.g.

I guess that is the best design option, for when you want to use
a Lisp expression.  But the simple case should be a string -- perhaps
a format string.

Stefan wrote:

    Yes, and if the use of `lambda' turns out to be a bit heavy, we can
    provide a handy alternative: if the return-spec is a list but not
    a function, then take the list as a function call with a missing argument:

I don't like that idea, because an incomplete form like this
seems like too fundamental a change in the Lisp way of doing things.