PLT Scheme sort function

Posted by Danny on Stack Overflow See other posts from Stack Overflow or by Danny
Published on 2010-02-03T16:22:41Z Indexed on 2010/06/08 2:12 UTC
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plt-scheme

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drscheme

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racket

PLT Scheme guide says that it's implemented sort function is able to sort a list according to an extarcted value using a lambda function. link text

The guide provides an unworking code example of this-

(sort '(("aardvark") ("dingo") ("cow") ("bear"))
      #:key car string<?)

Which returns an error.

How is this function is supposed to be calles so that it will actually sort a list according to values calculated by a given function?

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