greg <[EMAIL PROTECTED]> writes: > Douglas Alan wrote: >> greg <[EMAIL PROTECTED]> writes: > >>> This holds for *all* languages that I know about, both static and >>> dynamic. > >> Then you don't know about all that many languages. There are >> languages that use call-by-name, and those that use >> call-by-value-return. Some use call-by-need and others do >> call-by-macro-expansion. Etc. > > I didn't mean that these are the only two parameter passing > mechanisms in existence -- I know there are others.
I don't follow you. You stated that once you understand how assignment works, you understand the calling mechanism. That's just not true. Algol, for instance, did assignment-by-value but call-by-name. >> If I tell you, for instance, that Java, Python, Ruby, JavaScript, >> Lisp, and CLU all use call-by-sharing, then I have said something that >> makes a similarity among these languages easier to state and easier to >> grasp. > > If you told me they use "assignment by sharing", that would tell me > a lot *more* about the language than just talking about parameter > passing. Not really. Call-by-sharing virtually implies that the language does assignment-by-sharing. (I know of no counter-examples, and it is difficult to see how a violation of this rule-of-thumb would be useful in any new language.) Stating that a language does assignment-by-sharing does not imply that it does call-by-sharing. Or at least not exclusively so. Cf. certain dialects of Lisp. Also C#, which supports a variety of argument passing strategies. |>oug -- http://mail.python.org/mailman/listinfo/python-list
