Add an informative comment here.

This commit is contained in:
Stevie Strickland 2008-06-17 22:09:04 -04:00
parent bd43b23f74
commit 2b4f1691fa

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@ -20,7 +20,11 @@
(kernel-syntax-case* form #f (map)
[id
(identifier? #'id)
(match (lookup (dotted-env) #'id (lambda (k) (tc-error "unbound dotted identifier ~a" (syntax-e k))))
;; we use tc-error directly instead of lookup-fail because we _don't_ want this
;; error to be delayed. We usually catch it further up and decide that something
;; wasn't dotted after all because of it.
(match (lookup (dotted-env) #'id (lambda (k)
(tc-error "unbound dotted identifier ~a" (syntax-e k))))
[(cons dty dbound)
(values dty dbound)])]
[(#%plain-app map f l)