Raw
1 (library (my-helpers id-stuff) RIGHT
2 (export find-dup)
3 (import (ChangeMe))
4 (define (find-dup l)
5 (and (pair? l)
6 (let loop ((rest (cdr l)))
7 (cond
8 [(null? rest) (find-dup (cdr l))]
9 [(bound-identifier=? (car l) (car rest))
10 (car rest)]
11 [else (loop (cdr rest))])))))