Despite using it for a long time, I discovered today that I do not
understand 'curry', at least insofar as it applies to keyword
arguments.

> (define (baz a b) b)
> (baz 8 9)
9

> (curry baz 8)
#<procedure:curried>

> ((curry baz 8) 9)
9

> (define (foo a #:bar x) x)
> (foo 8 #:bar 9)
9

> (curry foo #:bar 9)
#<procedure:curried>

Up to this point I'm fine, but now my understanding derails and all is
confusion.

> ((curry foo #:bar 9) 8)
#<procedure:curried>

I expected it to yield 9 as it did in the original direct call.  The
curry records the keyword argument and returns a function that takes
one positional argument; when that argument is supplied the original
foo function has all the arguments it needs so it should execute.

Maybe if I apply the final curried proc as a thunk?

> (((curry foo #:bar 8) 9))
#<procedure:curried>

Nope.

What am I not understanding?

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