how to resolve this error "reference to an identifier before its definition: with"
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I am studying "Programming Languages: Application and Interpretation" and I can execute the first two chapters' examples in DrRacket 5.2.1 after executing "#lang plai". but when I typed the 3rd chapter's first example as below:
<pre><code>    (with (x 5) (+ x x))
</pre></code>
I got the following error:
reference to an identifier before its definition: with

please tell me how to resolve it!
Thanks a lot in advance!

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