[racket] "#%app: unbound identifier" error in DrRacket

From: Matthew Butterick (mb at mbtype.com)
Date: Sun Nov 9 02:06:48 EST 2014

Is it just me, or is DrRacket (, built from the current repo) frequently popping an error like this:

unsaved editor:3:0: #%app: unbound identifier; also, no #%app syntax transformer is bound at: #%app in: (#%app call-with-values (lambda () (quote 42)) print-values)

Seems to be endemic to:
+ unsaved source files.
+ source files with a (module+ main ...).
+ source files with rackunit tests.

The error doesn't prevent the file from running normally.

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