Stream command processing (long message)

[Bill Rozas <JINX%MIT-OZ@MIT-MC.ARPA>]

Why the syntax when
For a more complex example, SCP would translate the following:

filter-cstream symbol? <lists.scm | map-cstream list >single-level-list.scm

into

(call-with-output-file
    "single-level-list.scm"
    (filter-cstream
        (map-cstream
            (call-with-input-file
                "lists.scm"
                read-cstream)
            list)
        symbol?))