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rjshanley 24-Nov-2010 [3933x3] | Yes, it is. Native would be great. I just tried some simple stuff on R3 so I'll experiment further. Thanks a lot. |
R3 is a little wierd in its handling of large hex numbers - it displays them in scientific notation with limited precision instead of as integers. | |
>> 0x3333333333333 == 0x3.333333e12 | |
Sunanda 24-Nov-2010 [3936] | That's not a hex number. It's a REBOL pair. For hex, try this: to-hex 333333333333 |
Andreas 24-Nov-2010 [3937x3] | Which exposes a nice bug in A110. There is no longer an issue! type which can be used for arbitrary base literal numbers. |
So to-hex is actually rather misleading. | |
(And should probably be removed.) | |
BrianH 24-Nov-2010 [3940x2] | First of all, we never had a type that could be used for arbitrary base literal numbers, except the string types. |
Next, TO-HEX should probably not be removed, but it should return a string! instead. | |
Andreas 24-Nov-2010 [3942] | how would that differ from to-binary? |
BrianH 24-Nov-2010 [3943] | A binary is only formatted with hex characters (if the binary-base is 16). A string would actually containthe hex characters themselves. |
Andreas 24-Nov-2010 [3944x2] | So to-hex would be shortcut for enbase/base to-binary num 16. Rather useless. |
But my, why not. | |
BrianH 24-Nov-2010 [3946x2] | I expect that TO-HEX is a formatting function that is definitely not useless for web work, for example. |
That usage would require that we keep the issue-generating feature though, even if we couldn't convert back easily. | |
Andreas 24-Nov-2010 [3948] | Or you stop being lazy and add the # manually. |
BrianH 24-Nov-2010 [3949] | TO-HEX is a convenience function. Being lazy in a common situation is the whole point to convenience functions. |
Andreas 24-Nov-2010 [3950] | Being lazy means that there's no point to this discussion. |
BrianH 24-Nov-2010 [3951] | a nice bug in A110 - And which bug is that, exactly? Has it been reported? |
Andreas 24-Nov-2010 [3952] | Nevermind. |
BrianH 24-Nov-2010 [3953] | Trying to find out the bug is why I spoke up in the first place. I am trying to get the bugs reported so they can be fixed, as appropriate. It's amazing how often bugs go unreported and thus unfixed. |
Andreas 24-Nov-2010 [3954] | No bug. TO-HEX works as designed. Nothing to see here, move on people. |
BrianH 24-Nov-2010 [3955] | Ah, OK then. The change in issue! has brought up a lot of issues, so to speak. We are hoping to collect them all and come up with a set of tweaks and enhancements that can make things work. It should be possible to make them work a lot like they did before, with only minor changes (like being non-modifiable). You can replicate a lot of the behavior of a series type in a non-series type by simply having the series functions also work on the other type, as closely as appropriate. Good examples of these are SELECT and APPEND on objects and maps. |
Sunanda 25-Nov-2010 [3956] | I should have given the example: to-binary 33333333 As the above discussion suggests, creating an issue! is a bit of a dead end in this case. A binary! is much more usable.....That is true in R2 as well as R3. |
Duke 29-Nov-2010 [3957] | A function like: [code] func [x] [subtract 6 x] [/code] strikes me as being a lot like an anonymous function or lambda expression. Is that correct? How would I execute the above function from Rebol CLI? I keep getting error messages, so I'm not getting a piece of the puzzle. |
ChristianE 29-Nov-2010 [3958x3] | >> do func [x] [subtract 6 x] 1 == 5 >> apply func [x] [6 - x] [1] == 5 |
I'd say, yes, those are anonymous functions - in the sense that they aren't assigned to a word. But in the stricter sense of a "named" function, REBOL doesn't have that concept at all. You can assign a function to one word, some words, or no words at all. | |
Easy to see for example in code so simple as >> a: b: c: func [ ] [print "What's my name?"] >> do [a b c] | |
Izkata 29-Nov-2010 [3961] | I consider them to be the same as anonymous functions/lambdas, due to how I was introduced to that concept in Scheme - and a similar ability to have multiple words/names reference the same function, as ChristianE shows in Rebol: (define foo (lambda () (print "Hi")) (define bar foo) |
Duke 29-Nov-2010 [3962x2] | @Christian E. Thanks for the examples! In the first one, it just dawned on me that perhaps Rebol is a stack-based language - a bit like Forth et al. Didn't you just put "5" on the stack, then the "apply func" simply pops the the stack for its parameters? |
@Izkata Ithought that I smelled a lambda - maybe a la Rebol - but close enough :) | |
BrianH 29-Nov-2010 [3964] | REBOL has a stack, like most programming languages, but no explicit manipulation of it. DO function! just evaluates the arguments. One of the many gifts of using an interpreted language. |
Duke 29-Nov-2010 [3965] | @Brian So Rebol is not a stack-based language like Forth, or concatenative languages, like Joy, Cat etc? |
BrianH 29-Nov-2010 [3966] | Nope. I haven't used the others but like Cat a lot. Too bad the author has (temporarily?) abandoned the project. |
Duke 29-Nov-2010 [3967] | @Brian OK! I can get rid of _that_ mindset in trying to understand Rebol :) |
BrianH 29-Nov-2010 [3968] | REBOL is more like an interpreted Lisp, with a Forth-like direct binding model. |
Duke 29-Nov-2010 [3969] | @Brian kinda like newLisp, then - which I have dabbled in, and liked |
BrianH 29-Nov-2010 [3970x2] | newLisp is more compiled than REBOL, and has dynamic binding, which is a completely different concept. |
Unfortunately, it is a bit hard to explain direct binding to people already familiar with lexical or dynamic binding. | |
Duke 29-Nov-2010 [3972x2] | @Brian I hear you! Please don't try ;) now now. I'm still in the KISS mode as far as Rebol is concerned |
BTW, KISS refering to _me_ NOT you | |
BrianH 29-Nov-2010 [3974x2] | We all have our moments :) |
In the simple phase of your REBOL education, all you need to know is that we have something called "direct binding", where words have direct references to their values, but that in most cases it acts like lexical binding because we fake it. So write your code as if it's lexically bound until you run into problems, then come back and be new again for the next level :) | |
Duke 29-Nov-2010 [3976] | Cool! :) |
BrianH 29-Nov-2010 [3977] | I run into these next levels pretty often, usually after a conversation with Carl or Ladislav. It's no problem to be new again :) |
Ladislav 29-Nov-2010 [3978x3] | This looks simple enough to be readable just finely: http://blog.revolucent.net/2009/07/deep-rebol-bindology.html |
One thing that attracted my attention in the article: ...interesting fact about REBOL blocks: By default, their evaluation is deferred. - not being a native speaker, I do not know, whether it means the same as: ...interesting fact about REBOL blocks: They are not evaluated (i.e. understood as 'data', not as 'code'), unless an evaluation is explicitly requested. | |
(but that is just nitpicking from me, the text is fine) | |
BrianH 29-Nov-2010 [3981] | It's that terminology bug all over again. Good point, and good article. |
Steeve 29-Nov-2010 [3982] | Well, about binding in Rebol, it's not that hard to understand. The context of any word is a hidden property. Meaning it can be changed at any time. |
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