add text filtering and remove newlines from input (thanks natalia\!)

anna.scm

@@ -76,10 +76,19 @@
 (define (send-action stream chn action)
   (format stream "PRIVMSG ~a :\x01ACTION ~a\x01\r\n" chn action))
 
+(define (input-filter str)
+  (define (remove-newline lst)
+    (cond
+     ((or (null? lst)
+          (null? (cdr lst))) lst)
+     ((eq? (car lst) #\\) (remove-newline (cddr lst)))
+     (else (cons (car lst) (remove-newline (cdr lst))))))
+  (list->string (remove-newline (string->list str))))
+
 (define (evaluate str)
   (guard (ex
           (else (begin (display "error encountered!\n")
-                       'error)))
+                       'error))) ;; << this gets printed in chat
     (eval-in-sandbox (read (open-input-string str)))))
 
 (define (main-loop stream)
@@ -95,7 +104,8 @@
           (equal? ":!anna" (slist-ref data 3)))
       (send-message stream chn "Hello! I respond to !rollcall, !anna, and !eval <s-expr>."))
      ((equal? ":!eval" (slist-ref data 3))
-      (let* ((expr (string-concatenate (intersperse " " (cdr (member ":!eval" data))))))
+      (let* ((filtered-data (map input-filter data))
+             (expr (string-concatenate (intersperse " " (cdr (member ":!eval" filtered-data))))))
         (send-message stream chn (evaluate expr))))
      ((and (= 7 (length data))
            (equal? (list-tail data 4) '("ACTION" "shoots" "anna")))