[plt-scheme] Tricks with eval and namespaces

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Mon Aug 1 15:36:18 EDT 2005

At Mon, 1 Aug 2005 15:30:56 -0400 (EDT), Arjun Guha wrote:
> (module ill-typed-expressions mzscheme
>    [...]
>    (test/error
>     #'((define foo
>         (+ #t 43)))))
> However, when test/error evaluates, we get:
> ../../../../../../../u/garjun/.plt-scheme/299.106/collects/dungeon/r5rs/r5rs-
> tinfer.ss:40:11: 
> define-types-cgen: bad syntax in: (define-types-cgen (define-values (foo) 
> (+ #t 43)))
> The custom language doesn't bind define to anything, so we are vaguely 
> surprised that define is getting expanded to define-values.

The expression quoted with #' resides in a module that imports
`define', and #' preserves that context.

I think you want to strip all lexical context from the argument to
`test/error'. If you don't need source locations, then just use

  #,@(syntax-object->datum stx)

in place of 

  #, at stx

If you need to keep source location, then you'll need a traversal that
uses `syntax-e' and `(datum->syntax-object #f ....)'.


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