> On Oct 11, 2017, at 11:10 AM, George Neuner <gneun...@comcast.net>
> wrote:
> 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

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.


You received this message because you are subscribed to the Google Groups 
"Racket Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to racket-users+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to