Re: [Chicken-hackers] foreign-declare doesn't work with e.g. #<#END.

[Peter Bex]

On Wed, Sep 12, 2012 at 08:03:27AM -0500, Peter Danenberg wrote:
> It looks like foreign-declare doesn't work with multiline string
> constants with embedded expressions:
> 
>   (let ((program "R-test"))
>     (foreign-code
>      #<#END
>      Rf_initEmbeddedR(4, (char*[]) {"#{program}",
>                                     "--slave",
>                                     "--vanilla",
>                                     "--args"});
>   END
>   ))
> 
> results in:
> 
>   Syntax error: in `foreign-code' - string expected
> 
> Multiline string constants without embedded expressions work fine,
> however:
> 
>   (foreign-code
>    #<<END
>    Rf_initEmbeddedR(4, (char*[]) {"R-test",
>                                   "--slave",
>                                   "--vanilla",
>                                   "--args"});
>   END
>   )
> 
> Can this be considered a bug?

No, because these embedded expressions expand to code which dynamically
concatenates strings at runtime:

#;1> ,x (let ((program "R-test")) #<#END
"foo#{program}"
END
) 
(##core#let
  ((program "R-test"))
    (##sys#print-to-string (cons "\"foo" (cons program (cons "\"" '())))))

And foreign-code wants a string literal, at compile time.

Cheers,
Peter
-- 
http://sjamaan.ath.cx
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