On Wed, 11 Oct 2017 11:19:36 -0700, Alexis King
>> On Oct 11, 2017, at 11:10 AM, George Neuner <gneun...@comcast.net>
>> My (maybe wrong) reading of the docs suggests that to match a hash
>> table, the table must be defined inline in the match clause.
>This isn’t really accurate. The hash-table match pattern matches a hash
>table itself, but it sounds like you want to do something else, wanting
>to use a separate, known dictionary as a lookup table for
Hmm. For completeness? I'm having trouble imaging why you'd want to
match a literal hash table. Or boxes. The other options make more
sense. Oh well.
>To do this, you probably want the `app` match pattern:
> [(app (lambda (e) (dict-ref mydict e #f)) (? values val))
>That pattern will bind `val` to the result if it exists in the
>dictionary (and is non-#f). If you wanted this to be cleaner, you could
>wrap that pattern into a separate match expander.
I wish I'd been able to figure that out on my own. Perhaps there
should be another example that shows catching result value(s) and
doing something with them.
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