From 177dae090f633f516324968b719f55ebf2a60b3e Mon Sep 17 00:00:00 2001
From: Matthew Butterick <mb@mbtype.com>
Date: Tue, 28 Nov 2017 16:27:25 -0800
Subject: [PATCH] remove duplicates

---
 beautiful-racket-lib/br/define.rkt                    |  2 +-
 beautiful-racket-lib/br/private/generate-literals.rkt | 10 +++++-----
 beautiful-racket-lib/br/syntax.rkt                    |  5 +++--
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/beautiful-racket-lib/br/define.rkt b/beautiful-racket-lib/br/define.rkt
index 157ebe3..3dfb22d 100644
--- a/beautiful-racket-lib/br/define.rkt
+++ b/beautiful-racket-lib/br/define.rkt
@@ -149,7 +149,7 @@
            (λ (stx)
              (define result
                (syntax-parameterize ([caller-stx (make-rename-transformer #'stx)])
-                 (syntax-parse (syntax-case stx () [any #'any])
+                 (syntax-parse (if (syntax? stx) stx (datum->syntax #'here stx))
                      #:literals BOUND-LITS
                      #:datum-literals UNBOUND-LITS
                    [pat . result-exprs] ...
diff --git a/beautiful-racket-lib/br/private/generate-literals.rkt b/beautiful-racket-lib/br/private/generate-literals.rkt
index 9d44d36..3e262c4 100644
--- a/beautiful-racket-lib/br/private/generate-literals.rkt
+++ b/beautiful-racket-lib/br/private/generate-literals.rkt
@@ -22,13 +22,13 @@
              pat-arg))
 
 (define (generate-bound-and-unbound-literals pats #:treat-as-bound [bound-id #f])
+  (define literals (generate-literals pats))
   (define-values (bound-literals unbound-literals)
-    (partition identifier-binding (for/list ([pat (in-list (generate-literals pats))]
-                                             #:unless (and bound-id (bound-identifier=? pat bound-id)))
-                                            pat)))
+    (partition (λ (i) (or (identifier-binding i)
+                          (and bound-id (bound-identifier=? i bound-id)))) literals))
   ;; return as list of two lists so it's easy to match them in syntax pattern
-  (list (if bound-id (cons bound-id bound-literals) bound-literals)
-        unbound-literals))
+  ;; `syntax-parse` crabs if there are any duplicate ids, so remove them
+  (map (λ (ids) (remove-duplicates ids bound-identifier=?)) (list bound-literals unbound-literals)))
 
 (define (all-...-follow-wildcards pats)
   (define prev-datum (box #f))
diff --git a/beautiful-racket-lib/br/syntax.rkt b/beautiful-racket-lib/br/syntax.rkt
index 9b08e5c..38abc1c 100644
--- a/beautiful-racket-lib/br/syntax.rkt
+++ b/beautiful-racket-lib/br/syntax.rkt
@@ -39,10 +39,11 @@
 
 (define-macro (syntax-parse/easy STX LITS . EXPS)
   (with-syntax ([(BOUND-LITS UNBOUND-LITS) (generate-bound-and-unbound-literals #'LITS)])
-    #'(syntax-parse (syntax-case STX () [any #'any])
+    #'(let ([stx STX])
+        (syntax-parse (if (syntax? stx) stx (datum->syntax #'here stx))
         #:literals BOUND-LITS
         #:datum-literals UNBOUND-LITS
-        . EXPS)))
+        . EXPS))))
 
 (define-macro-cases pattern-case
   [(_ STX-ARG