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http://jmc.stanford.edu/articles/lisp/lisp.pdf http://jmc.stanford.edu/articles/lisp/lisp.pdf "One mathematical consideration that influenced LISP was to expre

by doall 9y ago

http://jmc.stanford.edu/articles/lisp/lisp.pdf http://jmc.stanford.edu/articles/lisp/lisp.pdf "One mathematical consideration that influenced LISP was to express programs as applicative expressions built up from variables and constants using functions. I considered it important to make these expressions obey the usual mathematical laws allowing replacement of expressions by expressions giving the same value. The motive was to allow proofs of properties of programs using ordinary mathematical methods. This is only possible to the extent that side-effects can be avoided. Unfortunately, side-effects are often a great convenience when computational efficiency is important, and “functions” with side-effects are present in LISP." Seems not black or white to me. This paper is also written by McCarthy. He had pureness in his mind, but the real implementation had side-effects for practical reasons. >McCarthy's original conception of Lisp was not purely functional (according to McCarthy himself as well as the historical evidence) Again not black or white (according to McCarthy himself). The pure language is written in the original LISP paper and Graham and I viewed it as the core and it also showed the pureness of LISP. >so how would the purely functional subset described in a later paper be "the original LISP" if you aren't denying the earlier work? Again the definition. I have already explained what I meant with "the original LISP".

kbp 9y ago
> > so how would the purely functional subset described in a later paper be "the original LISP" if you aren't denying the earlier work? > Again the definition. I have already explained what I meant with "the original LISP". I didn't ask what you meant by it, I asked how using that definition is different from claiming that McCarthy's earlier work on Lisp wasn't Lisp. In the same paper you just quoted, McCarthy says that Lisp was planned to have sequential programs before it was planned to have recursive functions; the part you quoted does not say that destructive functions were added later or that he ever planned not to have them. In the 1958 paper, he was already describing a language with mutable objects.
- doall 9y ago
  >McCarthy's earlier work on Lisp wasn't Lisp. I didn't say this. I have already explained about the difference between the first LISP implementation and the core language written in the 1960 paper. There is no one true definition of LISP and I have already talked about this. People have different views of what LISP is. You said black and white and it is not true from the paper I have shown. >In the 1958 paper, he was already describing a language with mutable objects. I am not talking about the 1958 paper. I am not also talking about which idea is first or not. Since it is not written clearly in the papers shown so far which idea is first, but I have showed that it is not black or white. Graham and my claim is based on the so called "original LISP paper" in 1960 and the pure version of LISP is written in it. You and I have different views of LISP and that is OK. But please don't force your view to us, since there is no one true definition or interpretation of LISP.
  - deleted 9y ago
    [deleted]
  - kbp 9y ago
    > >McCarthy's earlier work on Lisp wasn't Lisp. > I didn't say this. Again, I was asking how what you did say was different from it. Your answer seems to just be that your definition of Lisp means the subset described in the 1960 paper, and doesn't include the original implementation or McCarthy's earlier writing on the subject. > You said black and white and it is not true from the paper I have shown. The paper you quoted said that Lisp was originally conceived as an impure language (the part I quoted) and that that was unfortunate, but true (the part you quoted). > I have already explained about the difference between the first LISP implementation and the core language written in the 1960 paper. [...] I am not talking about the 1958 paper. So you meant to say that the 1960 paper was the first description of a pure language. Calling the 1960 paper's subset of Lisp "the original LISP" and disregarding the already-existing implemented Lisp system which the paper acknowledges, as well as McCarthy's previous writing on the subject, is misleading at best. > I am not also talking about which idea is first or not. Then we have different definitions of "original," too.
    - doall 9y ago

by doall 9y ago

kbp 9y ago

> > so how would the purely functional subset described in a later paper be "the original LISP" if you aren't denying the earlier work? > Again the definition. I have already explained what I meant with "the original LISP". I didn't ask what you meant by it, I asked how using that definition is different from claiming that McCarthy's earlier work on Lisp wasn't Lisp. In the same paper you just quoted, McCarthy says that Lisp was planned to have sequential programs before it was planned to have recursive functions; the part you quoted does not say that destructive functions were added later or that he ever planned not to have them. In the 1958 paper, he was already describing a language with mutable objects.

doall 9y ago
>McCarthy's earlier work on Lisp wasn't Lisp. I didn't say this. I have already explained about the difference between the first LISP implementation and the core language written in the 1960 paper. There is no one true definition of LISP and I have already talked about this. People have different views of what LISP is. You said black and white and it is not true from the paper I have shown. >In the 1958 paper, he was already describing a language with mutable objects. I am not talking about the 1958 paper. I am not also talking about which idea is first or not. Since it is not written clearly in the papers shown so far which idea is first, but I have showed that it is not black or white. Graham and my claim is based on the so called "original LISP paper" in 1960 and the pure version of LISP is written in it. You and I have different views of LISP and that is OK. But please don't force your view to us, since there is no one true definition or interpretation of LISP.
- deleted 9y ago
  [deleted]
- kbp 9y ago
  > >McCarthy's earlier work on Lisp wasn't Lisp. > I didn't say this. Again, I was asking how what you did say was different from it. Your answer seems to just be that your definition of Lisp means the subset described in the 1960 paper, and doesn't include the original implementation or McCarthy's earlier writing on the subject. > You said black and white and it is not true from the paper I have shown. The paper you quoted said that Lisp was originally conceived as an impure language (the part I quoted) and that that was unfortunate, but true (the part you quoted). > I have already explained about the difference between the first LISP implementation and the core language written in the 1960 paper. [...] I am not talking about the 1958 paper. So you meant to say that the 1960 paper was the first description of a pure language. Calling the 1960 paper's subset of Lisp "the original LISP" and disregarding the already-existing implemented Lisp system which the paper acknowledges, as well as McCarthy's previous writing on the subject, is misleading at best. > I am not also talking about which idea is first or not. Then we have different definitions of "original," too.
  - doall 9y ago