From 41e07b0cc6c8db0eae1e986037d1fe1e6e5c4fe6 Mon Sep 17 00:00:00 2001
From: Jay McCarthy <jay@racket-lang.org>
Date: Tue, 19 Mar 2013 08:58:32 -0600
Subject: [PATCH] Removing even/odd reading hack and just protecting parser
 from eof-ing ports

---
 collects/datalog/lang/configure-runtime.rkt | 22 ++++++++++-----------
 collects/racklog/lang/configure-runtime.rkt | 22 ++++++++++-----------
 2 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/collects/datalog/lang/configure-runtime.rkt b/collects/datalog/lang/configure-runtime.rkt
index 25e9ad3f93..eb066a168b 100644
--- a/collects/datalog/lang/configure-runtime.rkt
+++ b/collects/datalog/lang/configure-runtime.rkt
@@ -1,20 +1,18 @@
 #lang racket/base
 
 (define (configure data)
-  ;; (printf "Configuring\n")
-  (current-read-interaction even-read))
+  (current-read-interaction the-read))
 (provide configure)
 
 (require datalog/parse
          datalog/private/compiler)
 
-; XXX This is almost certainly wrong.
-(define (even-read src ip)
-  (begin0
-    (compile-statement
-     (parameterize ([current-source-name src])
-       (parse-statement ip)))
-    (current-read-interaction odd-read)))
-(define (odd-read src ip)
-  (current-read-interaction even-read)
-  eof)
+(define (the-read src ip)
+  (cond
+    [(or (not (char-ready? ip))
+         (eof-object? (peek-char ip)))
+     eof]
+    [else
+     (compile-statement
+      (parameterize ([current-source-name src])
+        (parse-statement ip)))]))
diff --git a/collects/racklog/lang/configure-runtime.rkt b/collects/racklog/lang/configure-runtime.rkt
index 15e7164b51..8b3de8e3dd 100644
--- a/collects/racklog/lang/configure-runtime.rkt
+++ b/collects/racklog/lang/configure-runtime.rkt
@@ -1,20 +1,18 @@
 #lang racket/base
 
 (define (configure data)
-  ;; (printf "Configuring\n")
-  (current-read-interaction even-read))
+  (current-read-interaction the-read))
 (provide configure)
 
 (require datalog/parse
          racklog/lang/compiler)
 
-; XXX This is almost certainly wrong.
-(define (even-read src ip)
-  (begin0
-    (compile-statement
-     (parameterize ([current-source-name src])
-       (parse-statement ip)))
-    (current-read-interaction odd-read)))
-(define (odd-read src ip)
-  (current-read-interaction even-read)
-  eof)
+(define (the-read src ip)
+  (cond
+    [(or (not (char-ready? ip))
+         (eof-object? (peek-char ip)))
+     eof]
+    [else
+     (compile-statement
+      (parameterize ([current-source-name src])
+        (parse-statement ip)))]))