> It is brittle in any case because the "script" being loaded may call
> `read' in between.

True. Perhaps implementations should be required to buffer the whole
source code from stdin before reading any of it. Otherwise the results
may be "artistic" :)

> Anyway, I just wanted to say that the author of
> `fantastic-scheme' may have decided that `fantastic-scheme' called
> without a filename may read an R7RS top-level program from the
> standard input port because the command to start a REPL is
> `fantastic-repl'. :)

This may be a matter of personal preference, but I always find it
confusing when a Scheme implementation (or other language
implementation) comes with more than one command. It is hard to figure
out which one to use when, and what will happen if you accidentally use
the wrong one.