The Craft of Emacs: Evaluation: S-expressions and special forms- source listing

Here’s a copy of the code you’ve written:

(defunxx()
(interactive)
(get-buffer-create"*xx*")
(switch-to-buffer"*xx*")
(erase-buffer)
(xx--insert-line"Skeins")
(xx--insert-line"======")
(let((strands(read-string"No. strands: ")
)
(stitches(read-string"No. stitches: ")
)
)
(xx--insert-line(concat"No. strands: "strands)
)
(xx--insert-line(concat"No. stitches: "stitches)
)
(xx--insert-line(concat"No. skeins: "(number-to-string(xx--num-skeins(string-to-numberstrands)
(string-to-numberstitches)
)
)
)
)
)
)
(defunxx--insert-line(text)
(inserttext)
(newline)
)
(defunxx--num-skeins(strandsstitches)
(ceiling(/(float(*strandsstitches)
)
4800.0)
)
)

xx.el