Index: src/0dev.org/predictor/predictor.go
==================================================================
--- src/0dev.org/predictor/predictor.go
+++ src/0dev.org/predictor/predictor.go
@@ -139,12 +139,11 @@
 		if len(ctx.input) > 0 {
 			readCount = copy(output, ctx.input)
 
 			// Check whether we still have leftover data in the buffer :)
 			if readCount < len(ctx.input) {
-				copy(ctx.input[:readCount], ctx.input[readCount:])
-				ctx.input = ctx.input[:readCount]
+				ctx.input = ctx.input[:copy(ctx.input, ctx.input[readCount:])]
 			}
 			return readCount, nil
 		}
 
 		// This is single-iteration only but it is fine according to io.Reader's contract ?!