From b702ac3edd86c3dc09a457ead38fefd703a4f1b2 Mon Sep 17 00:00:00 2001
From: Eli Barzilay <eli@barzilay.org>
Date: Sat, 9 Oct 2004 21:29:30 +0000
Subject: [PATCH] extended hash-table to accept flags

original commit: 0963e8c203a548ba12f0af88bf1e7a5f1a498944
---
 collects/mzlib/etc.ss | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/collects/mzlib/etc.ss b/collects/mzlib/etc.ss
index 64fecc9..e583d71 100644
--- a/collects/mzlib/etc.ss
+++ b/collects/mzlib/etc.ss
@@ -496,14 +496,19 @@
 	  (syntax/loc stx
 	    (define-syntaxes (id ...)
 	      (finish-syntax-set orig-stx)))))]))
-  
+
   (define-syntax (hash-table stx)
-    (syntax-case stx ()
-      [(_ (key value) ...)
-       (syntax/loc stx
-         (let ([ht (make-hash-table)])
-           (hash-table-put! ht key value) ...
-           ht))]))
+    (syntax-case stx (quote)
+      [(_ x ...)
+       (let loop ([xs #'(x ...)] [flags '()])
+         (syntax-case xs (quote)
+           [('flag x ...) (loop #'(x ...) (cons #''flag flags))]
+           [([key val] ...)
+            (with-syntax ([(flag ...) (reverse flags)])
+              (syntax/loc stx
+                (let ([ht (make-hash-table flag ...)])
+                  (hash-table-put! ht key val) ...
+                  ht)))]))]))
 
   (define-syntax (begin-with-definitions stx)
     ;; Body can have mixed exprs and defns. Wrap expressions with