[plt-scheme] example of match quasipattern

From: Jens Axel Søgaard (jensaxel at soegaard.net)
Date: Fri Aug 23 03:10:07 EDT 2002

Jens Axel Søgaard wrote:
> I  expected this to work:
>   > (let ([sym 'duck])
>       (match '(duck dog)
>         [`(',sym rest) rest]))
>   . match: no matching clause for (duck dog)
> But it doesn't. I just wish I could see why.

Ah. In the quasipattern the sym pattern matches sym.
The value of sym is looked up. That's what you meant
by escaping to scheme.

Jens Axel Søgaard

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