Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!ukc!dcl-cs!aber-cs!athene!pcg From: pcg@test.aber.ac.uk (Piercarlo Antonio Grandi) Newsgroups: comp.lang.scheme Subject: Re: To Lisp, or not to Lisp; that is the question. Message-ID: Date: 13 Mar 91 19:10:08 GMT References: <9103080432.AA06368@kolyma> <455@data.UUCP> <4299@skye.ed.ac.uk> Sender: aro@aber-cs.UUCP Organization: Coleg Prifysgol Cymru Lines: 36 Nntp-Posting-Host: aberdb In-reply-to: jeff@aiai.ed.ac.uk's message of 11 Mar 91 18:23:32 GMT On 11 Mar 91 18:23:32 GMT, jeff@aiai.ed.ac.uk (Jeff Dalton) said: jeff> But the language / environment distinction is also used _against_ jeff> Lisp. For example, I've heard people claim that no one really likes jeff> Lisp as a language. It's the the _environment_ they like. [I think jeff> this claim is false, by the way.] Actually I think exactly the opposite; I love Scheme (and Lisp) as *languages*, and I think that their usual environments are regrettably overdone and isolated from the larger environment in which they are run, and so on. jeff> I do not agree that EVAL is environment. EVAL might be provided as jeff> part of the environment in Scheme -- because it's not part of the jeff> language. But that does not mean it is inherently environmental. EVAL is the "compiler", really. An argument can be made that the 'C' environment is the whole of Unix, yet, so maybe since you can after all in 'C' write things to a file and then 'system("cc -c ...");' you can claim you have eval in 'C', in its environment, just like Scheme. jeff> In most Lisps, it is part of the language. In this it is jeff> different from LOAD. EVAL is not just another way to get programs jeff> into execution. It is not just an alternative to LOADing them, or jeff> typing "lisp " to the shell. It depends on whether you look at the Lisp implementation as a virtual machine on its own, or on whether you see it as amodule of the environment of the underlying OS. In the former case, EVAL is indeed part of the 'language' :-). -- Piercarlo Grandi | ARPA: pcg%uk.ac.aber@nsfnet-relay.ac.uk Dept of CS, UCW Aberystwyth | UUCP: ...!mcsun!ukc!aber-cs!pcg Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@aber.ac.uk