diff --git a/src/evalbuffer.c b/src/evalbuffer.c
index 3fed389..2ba2f67 100644
--- a/src/evalbuffer.c
+++ b/src/evalbuffer.c
@@ -128,7 +128,8 @@
 }
 
 /*
- * Set line or list of lines in buffer "buf".
+ * Set line or list of lines in buffer "buf" to "lines".
+ * Any type is allowed and converted to a string.
  */
     static void
 set_buffer_lines(
@@ -187,7 +188,7 @@
 	li = l->lv_first;
     }
     else
-	line = tv_get_string_chk(lines);
+	line = typval_tostring(lines, FALSE);
 
     // default result is zero == OK
     for (;;)
@@ -197,7 +198,8 @@
 	    // list argument, get next string
 	    if (li == NULL)
 		break;
-	    line = tv_get_string_chk(&li->li_tv);
+	    vim_free(line);
+	    line = typval_tostring(&li->li_tv, FALSE);
 	    li = li->li_next;
 	}
 
@@ -238,6 +240,7 @@
 	    break;
 	++lnum;
     }
+    vim_free(line);
 
     if (added > 0)
     {