1 files changed, 6 insertions, 1 deletions
diff --git a/stream.sig b/stream.sig
index 795d193..2bdb155 100644
--- a/stream.sig
+++ b/stream.sig
@@ -20,7 +20,12 @@ signature STREAM = sig
 
   val getPos: t -> pos
   val getPosAfterCharRead: t -> pos
+
+  (* pos must come from t, see pos2pposWithFI *)
   val pos2ppos: pos -> t -> ppos
+  (* #id pos must be equal to fileId of fileInfo,
+   * otherwise InvalidFileInfo is thrown *)
+  val pos2pposWithFI: pos -> fileInfo -> ppos
 
   (* Assumed to be called once for given pos, so will throw Unreachable on
    * second call *)
@@ -30,5 +35,5 @@ signature STREAM = sig
   val isFirstOnLine: pos -> t -> bool
 
   (* throws IO.Io *)
-  val streamInit: string -> t
+  val create: string -> t
 end