[plt-scheme] Re: What's the latest on the Scsh port?

From: Michael Burschik (Burschik at lotto-berlin.de)
Date: Tue Jul 15 03:26:37 EDT 2003

When designing an interactive shell, one should bear in mind that the desire
to keep keystrokes to a minimum led to the complexity of current unix
shells. And I consider this a mistake that does not need to be repeated.

Why should the command line parser change anything at all? Implied and
implicit parenthesis will only lead to unnecessary complexity while saving
two keystrokes per command line, which does not seem to be that high a price
to pay. So, in summary, I think

ls

should return the value of the variable ls, or signal an error if the symbol
is unbound,

(ls)

should call the procedure ls, or signal an error if the symbol is unbound,
and

(system "ls")

or something similar should call the external program ls, or signal an error
if such a program can not be found. Of course, (system "ls") is much more
cumbersome than simply ls, but I would assume that the most common commands
would be available as procedures, either implemented in scheme, or as
shortcuts for calling the external programs, e.g. (define ls (lambda ()
(system "ls"))).

Regards

Michael Burschik



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