Re: Goops, set! and define-syntax throuble

[Martin Grabmueller]

Hello,

I'm not an expert on goops, nor on high-level macros, but let me try
anyway...

> From: Ingo Ruhnke <address@hidden>
> Date: 06 Mar 2001 22:04:12 +0100

[snip]

> (my-begin 
>     (set! a 5)
>     (set! (somevar b) 5) ;; <- this line is causing throuble
>     (set-somevar b 5))
> -------------------------- snip --------------------------

The syntax (set! <setter> <value>) is a Guile extension (called
gerneralized set!), which is not supported by syntax-case, apparently.
syntax-case only allows the R5RS set! syntax.

> If I move "(set! (somevar b) 5)" outsite of my-begin it works, if I
> use set-somevar instead it also works, only when using set! inside
> my-begin it fails.  Anybody knows what is going on here?

The reason seems to be that the expansion of syntax is only invoked
inside of a syntax-case macro expansion.

HTH,
  'martin