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define-match-expander
Version: 4.1

 (require mzlib/plt-match)

The mzlib/plt-match library mostly re-provides scheme/match.

(define-match-expander id proc-expr)

(define-match-expander id proc-expr proc-expr)

(define-match-expander id proc-expr proc-expr proc-expr)

The same as the form from mzlib/match.