... to Andre and Abdulaziz for their quick responses.  I'll fix the problems they noted and post revised code within the next few days.  Perhaps, instead of writing the first R6RS SRFI, I should have written the last R5RS SRFI, since I obviously don't understand R6RS as well as I thought.  There are test cases in the 
streams.ss file that is linked from the Implementation section just before the start of the code.<br><br>Apologies to &quot;van&quot; Tonder for spelling his name wrong.<br><br>Phil<br>