A little F# for you
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I've been studying F# a lot recently and find it really mind-bending. Tomas Petricek, a fellow CPian, let me sneak preview his series of F# articles and they are very good. I took one of his examples and modified it a bit. The following code displays "sum = 6", but how that happens is other-worldly...check it out:
#light
let rec sum nums =
match nums with
| head::tail -> head + sum(tail)
| [] -> 0
printf "sum = %i" (sum [1; 2; 3])Weird, eh? F# is coooool. :cool:
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
Strangely reminiscent of Lisp as well.
Deja View - the feeling that you've seen this post before.
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I've been studying F# a lot recently and find it really mind-bending. Tomas Petricek, a fellow CPian, let me sneak preview his series of F# articles and they are very good. I took one of his examples and modified it a bit. The following code displays "sum = 6", but how that happens is other-worldly...check it out:
#light
let rec sum nums =
match nums with
| head::tail -> head + sum(tail)
| [] -> 0
printf "sum = %i" (sum [1; 2; 3])Weird, eh? F# is coooool. :cool:
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
So, you're declaring a function called sum, and it's recursive (the rec part). It takes a parameter called nums. I see some pattern matching going on, but I start getting lost after that. :) Care to explain? *edit*, nevermind, I see you posted comments in another post that explain it. Thanks.
Tech, life, family, faith: Give me a visit. I'm currently blogging about: No, Not I - A poem by Holocaust escapee, chief rabbi, and Messiah-follower Daniel Zion The apostle Paul, modernly speaking: Epistles of Paul Judah Himango
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Josh Smith wrote:
Weird, eh? F# is coooool.
I think we need to explore your childhood, Josh. Marc
Marc Clifton wrote:
I think we need to explore your childhood, Josh.
:laugh: I was raised by a pack of wolves, and ate peyote for breakfast.
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
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So, you're declaring a function called sum, and it's recursive (the rec part). It takes a parameter called nums. I see some pattern matching going on, but I start getting lost after that. :) Care to explain? *edit*, nevermind, I see you posted comments in another post that explain it. Thanks.
Tech, life, family, faith: Give me a visit. I'm currently blogging about: No, Not I - A poem by Holocaust escapee, chief rabbi, and Messiah-follower Daniel Zion The apostle Paul, modernly speaking: Epistles of Paul Judah Himango
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
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F# you too.
Faith is a fine invention For gentlemen who see; But microscopes are prudent In an emergency! -Emily Dickinson
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John Simmons / outlaw programmer wrote:
Looks like a bastardization of dBase2 and interpreted basic.
Something tells me that you won't be an F# "early adopter." :)
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
If it took me almost 7 years to start coding in .net, you can imagine how excited I am about F#...
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
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"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001 -
Marc Clifton wrote:
I think we need to explore your childhood, Josh.
:laugh: I was raised by a pack of wolves, and ate peyote for breakfast.
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
Josh Smith wrote:
I was raised by a pack of wolves
we might be related! ;P
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
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Ravel H. Joyce wrote:
But no, I won't do anything like that. I promise.
Ok good. Like I said you are a very smart kid, and drugs would only ruin your hopes, dreams, and your desire to be a good, honest person. It will kill your zest for life! You really should remove that Hansen song from your signature though, and stop listenting to that crap. That will also ruin your life!:laugh::laugh::laugh::cool:
I get all the news I need from the weather report - Paul Simon (from "The Only Living Boy in New York")
Justin Perez wrote:
stop listenting to that crap
:suss: ... ... ... ...I almost didn't change it, you know...'Mmmbop' is fun! You're killing my zest for life.
"Who wants waffles? We got a new album out...it's called 10,000 Days. Buy it so I can afford waffles." -Maynard James Keenan
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ph'nglui magl'nath cthulhu r'lyeh wagn'nagl fhtagn
-- If you view money as inherently evil, I view it as my duty to assist in making you more virtuous.
yes, but the big question is... is He dreaming of F#?
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
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Strangely reminiscent of Lisp as well.
Deja View - the feeling that you've seen this post before.
everything old is new again....
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
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Not very different than prolog or scheme (my favorite language). Prolog:
sum([X | Y], Z) :- sum(Y, A), Z is A + X.
sum([], 0).Scheme:
(define sum (lambda (x)
(if (null? x) 0 (+ (car x) (sum (cdr x))))))Co-Author ASP.NET AJAX in Action
Scheme and its never ending parens reminds me of this XKCD on Lisp[^]. :)
Tech, life, family, faith: Give me a visit. I'm currently blogging about: No, Not I - A poem by Holocaust escapee, chief rabbi, and Messiah-follower Daniel Zion The apostle Paul, modernly speaking: Epistles of Paul Judah Himango
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yes, but the big question is... is He dreaming of F#?
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
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I've been studying F# a lot recently and find it really mind-bending. Tomas Petricek, a fellow CPian, let me sneak preview his series of F# articles and they are very good. I took one of his examples and modified it a bit. The following code displays "sum = 6", but how that happens is other-worldly...check it out:
#light
let rec sum nums =
match nums with
| head::tail -> head + sum(tail)
| [] -> 0
printf "sum = %i" (sum [1; 2; 3])Weird, eh? F# is coooool. :cool:
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
Grown bored with WPF now have you? No challenges left there?
Deja View - the feeling that you've seen this post before.
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Justin Perez wrote:
stop listenting to that crap
:suss: ... ... ... ...I almost didn't change it, you know...'Mmmbop' is fun! You're killing my zest for life.
"Who wants waffles? We got a new album out...it's called 10,000 Days. Buy it so I can afford waffles." -Maynard James Keenan
Ravel H. Joyce wrote:
...I almost didn't change it, you know...'Mmmbop' is fun! You're killing my zest for life.
Haha sorry man, you can keep it in your sig! :rolleyes:
I get all the news I need from the weather report - Paul Simon (from "The Only Living Boy in New York")
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dan neely wrote:
nah, malbolge[^]
:doh::doh: I had heard of that, but never looked to see what it was.... :doh::doh:
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
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Grown bored with WPF now have you? No challenges left there?
Deja View - the feeling that you've seen this post before.
Pete O'Hanlon wrote:
Grown bored with WPF now have you?
Argh! Don't say that!! I, too, feel that I "must remain" pidgeon-holed into WPF. But I don't want to feel trapped like that. I am a bit tired of WPF at the moment, considering that I've studied nothing else for the past two years! Plus, part of my agenda[^] is to see if/how F# and WPF can work together.
Pete O'Hanlon wrote:
No challenges left there?
Yeah right. I've only scratched the surface.
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
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Ravel H. Joyce wrote:
...I almost didn't change it, you know...'Mmmbop' is fun! You're killing my zest for life.
Haha sorry man, you can keep it in your sig! :rolleyes:
I get all the news I need from the weather report - Paul Simon (from "The Only Living Boy in New York")
Nah, I like Maynard. I admire him perhaps more than anybody else. Not that I would ever tell anyone such a thing... :doh:
"Who wants waffles? We got a new album out...it's called 10,000 Days. Buy it so I can afford waffles." -Maynard James Keenan
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Pete O'Hanlon wrote:
Grown bored with WPF now have you?
Argh! Don't say that!! I, too, feel that I "must remain" pidgeon-holed into WPF. But I don't want to feel trapped like that. I am a bit tired of WPF at the moment, considering that I've studied nothing else for the past two years! Plus, part of my agenda[^] is to see if/how F# and WPF can work together.
Pete O'Hanlon wrote:
No challenges left there?
Yeah right. I've only scratched the surface.
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
Josh Smith wrote:
I've only scratched the surface.
of WPF or F#?:rolleyes:
Co-Author ASP.NET AJAX in Action
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I've been studying F# a lot recently and find it really mind-bending. Tomas Petricek, a fellow CPian, let me sneak preview his series of F# articles and they are very good. I took one of his examples and modified it a bit. The following code displays "sum = 6", but how that happens is other-worldly...check it out:
#light
let rec sum nums =
match nums with
| head::tail -> head + sum(tail)
| [] -> 0
printf "sum = %i" (sum [1; 2; 3])Weird, eh? F# is coooool. :cool:
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
Oh...I remember this. In my Programming Languages class when we did ML....*shivers* Right when I saw "head::tail" and the recursive call. I would like to see a whole application written in this, though. - Keith
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leppie wrote:
Wouldnt that just destructure your input list into 'head' and 'tail' variable? Perhaps the '::' has special meaning?
Keep in mind, I've only been studying F# for a few days now. But, my current understanding is that F# uses the x::y syntax for dealing with its "list" type. You can create a list, or pull one apart, with that :: operator. AFAIK, writing "head::tail" (or foo::goo) is a way of saying "Give me the first cell in the list, and then also give me the remainder of the list."
:josh: My WPF Blog[^] Without a strive for perfection I would be terribly bored.
Ahh so it similar to to Scheme/Lisp's
.operator :)xacc.ide
The rule of three: "The first time you notice something that might repeat, don't generalize it. The second time the situation occurs, develop in a similar fashion -- possibly even copy/paste -- but don't generalize yet. On the third time, look to generalize the approach."