fix bug introduced in 6b2a4ff5

collects/syntax/readerr.rkt

@@ -30,6 +30,7 @@
       (format "~a~a"
               (cond [(not (error-print-source-location)) ""]
                     [(srcloc->string (srcloc source-name line col pos span))
+                     =>
                      (lambda (s)
                        (format "~a: " s))]
                     [else ""])

collects/tests/syntax/test-readerr.rkt

@@ -0,0 +1,9 @@
+#lang racket/base
+(require rackunit syntax/readerr)
+
+(check-exn
+ (λ (x) 
+   (and (exn:fail:read:eof? x)
+        (regexp-match #rx"^y[01: ]* x" (exn-message x))))
+ (λ () (raise-read-eof-error
+        "x" "y" 1 1 1 1)))