The following expression should do what you want: (+ (string->number "1.2") 1) If you're starting from a symbol, use symbol->string before string->number. Carl Eastlund <div class="gmail_quote">On Mon, Sep 10, 2012 at 12:41 PM, Nikolaus Klepp <<a href="mailto:dr.klepp@gmx.at" target="_blank">dr.klepp@gmx.at</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Hi all, In tinyscheme I can do this: > (+ (string->symbol "1.2") 1) 2.2 In racket that does not work, because > (string->symbol "1.2") '|1.2| which is not a number. I can use this workaround: > (+ (read (open-input-string "1.2")) 1) 2.2 But is there a clean way to get the above line from tinyscheme working on racket without that workaround? Nik </blockquote></div>