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On Thu, 14 Feb 2008 20:06:39 +0000, Orchid XP v7 wrote:
>>> Well *obviously* I actually meant to type 35...
>>
>> What, even with separate keys on the keyboard? <scnr> <g>
>
> Care to count how many characters I typed *correctly*? ;-)
Nah, I just couldn't resist the temptation to call you on it. ;-)
Jim
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>> As the name suggests, it's a language specifically designed to be
>> incomprehensible. [Unlike, say, the SKI calculus, which *is*
>> incomprehensible, but not by design...]
>
> Well, yes, but at the same time, there must be a definitive reference on
> it. Or is it the "ipsum lorem" text that's considered definitive? ;-)
Oh yes, of course...
http://www.muppetlabs.com/~breadbox/bf/
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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> So what's the difference? Well, let's try this:
>
> function solve2(a, b, c)
> {
> var det = Math.sqrt(det2);
> var det2 = b*b - 4*a*c;
> var a2 = 2*a;
> return Array((0-b-dat)/a2, (0-b+det)/a2));
> }
>
> Hmm, that's not going to work properly... However, the corresponding
> Haskell works exactly as before:
>
> solve2 a b c =
> let det = sqrt det2
> det2 = b*b - 4*a*c
> a2 = 2*a
> in [(0-b-det)/a2, (0-b+det)/a2]
>
> So in Haskell, the ordering doesn't matter.
http://rinkworks.com/stupid/cs_programming.shtml
"An introductory programming student once asked me to look at his
program and figure out why it was always churning out zeroes as the
result of a simple computation. I looked at the program, and it was
pretty obvious:
begin
readln("Number of Apples", apples);
readln("Number of Carrots", carrots);
readln("Price for 1 Apple", a_price);
readln("Price for 1 Carrot", c_price);
writeln("Total for Apples", a_total);
writeln("Total for Carrots", c_total);
writeln("Total", total);
total := a_total + c_total;
a_total := apples * a_price;
c_total := carrots + c_price;
end;
* Me: "Well, your program can't print correct results before they're
computed."
* Him: "Huh? It's logical what the right solution is, and the computer
should reorder the instructions the right way."
---
So he was right after all...
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Orchid XP v7 <voi### [at] dev null> wrote:
> >> Brainf*ck.
> >
> > Now there's a language I'm unfamiliar with - who wrote the book on that
> > one? ;-)
> As the name suggests, it's a language specifically designed to be
> incomprehensible.
Personally I like the idea behind Befunge more. The only problem I have
with Befunge is that it's way too difficult to do anything practical with
it (because it uses a stack which you can't index, and it lacks support
for variables).
--
- Warp
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Warp <war### [at] tagpovrayorg> wrote:
> I asked because 'let' sounded to me like an assignment, which is not
> functional.
it introduces a new lexically scoped binding for a constant "function". It's
not like you can't give values names in functional languages. Come on, giving
names is the simplest means of abstraction there is!
Assignment is only bad when it happens all the time, at all levels, by multiple
points in code mutating a single location, which can lead to undesired
side-effects as the source of many bugs and sync problems. As a rule of thumb,
in functional languages new locations are created rather than altering the
contents of previous ones, unless when it's not wise on the performance side.
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>> So in Haskell, the ordering doesn't matter.
>
> http://rinkworks.com/stupid/cs_programming.shtml
>
> "An introductory programming student once asked me to look at his
> program and figure out why it was always churning out zeroes as the
> result of a simple computation. I looked at the program, and it was
> pretty obvious:
>
> begin
> readln("Number of Apples", apples);
> readln("Number of Carrots", carrots);
> readln("Price for 1 Apple", a_price);
> readln("Price for 1 Carrot", c_price);
> writeln("Total for Apples", a_total);
> writeln("Total for Carrots", c_total);
> writeln("Total", total);
> total := a_total + c_total;
> a_total := apples * a_price;
> c_total := carrots + c_price;
> end;
>
> * Me: "Well, your program can't print correct results before they're
> computed."
> * Him: "Huh? It's logical what the right solution is, and the computer
> should reorder the instructions the right way."
>
> ---
>
> So he was right after all...
The trouble is, as soon as you start assigning more than one value to
something, it suddenly matters *when* you read it's value. And that
means if you start reordering things, everything goes horribly wrong.
Haskell does not permit you to assign more than one value to any given
variable. Thus, Haskell is able to chase down dependencies (even
circular ones) and Do The Right Thing(tm). So it really is a math-style
definition that always holds rather than an imperative-style assignment
at a specific point in time.
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Orchid XP v7 <voi### [at] devnull> wrote:
> solve2 a b c =
> let det = sqrt det2
> det2 = b*b - 4*a*c
> a2 = 2*a
> in [(0-b-det)/a2, (0-b+det)/a2]
I wonder what something along the lines of this would do:
foo a =
let res = if a<2 then 1 else a*foo(a-1)
in res
--
- Warp
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Orchid XP v7 <voi### [at] devnull> wrote:
> > I asked because 'let' sounded to me like an assignment, which is not
> > functional.
>
> I'm pretty sure you're right about Lisp. But in Haskell, it's not an
> assignment - although it does look like one.
In Scheme and Lisp, let introduces new lexical scoped bindings for values, just
like in Haskell. Except someone can use set! on them and break all referential
transparency apart...
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Orchid XP v7 <voi### [at] devnull> wrote:
> And how do you suggest I do that, given that there's no obvious "entry
> point"?
run one of them, perhaps "un", on some RSA key?
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Nicolas Alvarez wrote:
> http://rinkworks.com/stupid/cs_programming.shtml
Woah. Some of these are pretty "special" BTW... :-D
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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