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2 points by zck 810 days ago | link | parent

> But I shouldn't have to invoke make-list with a nil list to begin with.

You can use a helper function:

    (def make-list (size val)
         (make-list-helper nil size val))
    
    (def make-list-helper (alist size val)
         (if (is size 1)
             (cons val alist)
           (make-list-helper (cons val alist) (- size 1) val)))
But this clutters up the namespace. We can use a local helper function to move make-list-helper inside the body of make-list, and wrap it in afn to make it able to recurse.

    (def make-list (size val)
         (let helper (afn (alist size val)
                          (if (is size 1)
                              (cons val alist)
                            (self (cons val alist) (- size 1) val)))
              (helper nil size val)))