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Re: [Scheme-reports] Draft 3 Comments: Chapter 6
On Thu, Aug 4, 2011 at 12:46 PM, John Cowan <cowan@x> wrote:
> Alex Shinn scripsit:
>> The initial (or "top level") Scheme environment is empty, and
>> bindings must be introduced with import.
>> which could indeed be worded better - the implication of the
>> second clause is that `import' is provided. The initial
>> environment is indeed empty of everything other than `import'.
> However, the "initial environment" is *not* the environment in effect
> when the REPL starts up. That includes at least the base and optionally
> whatever the implementation wishes to provide.
> In fact, I do not know what "initial environment" means at all.
It's the environment programs start with.
The result is that any program can be cut&paste into
an interactive REPL and still work, and any interactive
session can be saved and used as a program, so long
as it's prefixed with (import (scheme base)).
It would be cleaner to make the initial REPL env
empty as well (and cleaner still to make importing
out-of-band as in Scheme48), but this contradicts
every existing REPL and would be confusing for
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