The previous definition of define-simple-macro would fail (with
a very poor error message) if the user made a simple macro like:
(define-simple-macro (~or a b)
(let ([tmp a])
(if tmp tmp b)))
While the define-simple-macro form does allow syntax-parse patterns,
this should not be enabled for the initial head pattern, as described
in the define-simple-macro documentation.
* byte-regexp? values should not be considered 3D syntax.
* hash? values are now allowed in serialized syntax properties with (template … #:properties (…))
* marshalling properties which were prefab structs called map on the result of struct->vector, changed it to struct->list as the struct "name" is always serializable.
This change permits EH patterns like (~once <nullable>), because the
match will happen at most once, so there is no danger of divergence.
Thanks to Alex Knauth for pointing out this special case.
Merge to release branch.
The symbol is used as the "who" field in the error message.
Also fix lazy-require of runtime-report.rkt in residual.rkt; don't
load until syntax-parse actually needs to produce an error report.
(Previously was loaded to create handler whenever syntax-parse code ran.)
