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[REBOL] Re: Slashdot REBOL mention

From: rotenca:telvia:it at: 31-Oct-2001 16:33

> Example #2 Rebol PARSE function. Let's have a block: > > block: [copy result telephone] > > If we simply DO this block, we are evaluating the COPY function that should > set 'result to refer to a copy of TELEPHONE. If we instead use block as a > parse rule, BLOCK would have totally different meaning. Namely, 'result > would be set to a copy of a part of PARSE INPUT argument that would satisfy > the TELEPHONE subrule. The difference isn't that big, but it is only > natural, that 'copy should always communicate similar meaning, isn't it? > > There is a whole lot of native Rebol dialects, examples:
I like to think that: [copy result telephone] has no meaning before the program give it one. There are not keywords (words with fixed meanings). Before DO-ing it, you must give a meaning to the words of that block, binding them to a context. Everything is a dialect in Rebol.
> The existence of dialects doesn't distinguish these languages. The real > difference is, that we can define our own REBOL dialects (using PARSE e.g.),
Parse can be util to change the syntax, like in the parse dialect itself, where set-word and get-word have a different use, but context is the key for meaning: x: [copy result telephone] bind x in context [copy: :+ result: 3 telephone: 5] 'self ; now the words in x have others meanings until we re-bind them do x bind x in context [copy: :view result: :layout telephone: [button ""]] 'self do x
> A "buzzword" that communicates this meaning is, that REBOL is a language > with meta-circular semantics. This feature makes the language much more > communicative than any other language not having this feature is.
Semantic -> bind, parse cannot directly change the meaning of a word. Fixed, in Rebol, are only some syntax rules: the use of "[]", of "()", strings {}, set-word, get-word, comment ; and little more. Datatypes are almost fixed (to-word is not datatype aware) but only because RT did not give us the mode to change the load function to change/add/remove some datatypes.
> Ladislav
--- Ciao Romano