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Well, I don't know about that . . . lisp seems pretty supernatural to me.


Thank you! I don't think there's any example of a systems which fulfills the desired properties of a Blockchain without a native cryptocurrency. I'm skeptical of the notion of intrinsic worth. I think things have value because humans value them. Gold has a lot of utility, you probably use it frequently without knowing it. I think it's more accurate to say that Blockchain uses Bitcoin, since Blockchain was the solution necessary to create Bitcoin(speaking of course before the advent of derivative cryptocurrencies+blockchains), but really they're codependent. You need bitcoin to write to Bitcoin's blockchain. That's very useful.


1 point by i4cu 12 days ago | link

> You need bitcoin to write to Bitcoin's blockchain.

Right so, Blockchain is a methodology for a cryptographic system of record with transaction capability, and doesn't have to be used for currency, even though that's how everyone is using it. When you simplify it down to a 'system of record' then other use cases become new opportunities. I don't currently have useful ideas outside of currency, but my point was that Buffet doesn't need to understand the details of the methodology (bottom up) to establish an understanding of Bitcoin for investment purposes.

Even as a currency it is valuable provided that it gets tied to something tangible/meaningful. Personally I'm interested in ethereum because of its smart contracts and dapps.

> Gold has a lot of utility,

I'm aware that gold has some utility, so you are correct that I shouldn't haven't stated 'no utility', but gold's utility is not capable of justifying the price on the market. If gold was not being held as asset for the sake of being held as an asset, based on its rarity, then its market value would plunge to the near bottom.

> I'm skeptical of the notion of intrinsic worth. I think things have value because humans value them.

Right so, Gold has value because humans value it, but its value on the market is not tied to its intrinsic worth it's tied to its rarity alone. And that's the point of highlighting intrinsic worth over a human valuation. The value stability/durability is tied to its intrinsic worth.

The overall point is that Buffet is a value investor that's known to use intrinsic worth as the value measure. This is why Buffet hates both gold and Bitcoin. So let's not assume that he doesn't understand. Bitcoin's value is not stable because it's not tied to anything tangible. Even $ are just notes, but they are backed by a gov't which is why they have intrinsic value and therefore much more stability (or as much stability as the gov't/country provides).

note: made some edits to support correct word use.


1 point by kinnard 928 days ago | link | parent | on: How Lisp is going to save the world!

This is awesome.


1 point by kinnard 946 days ago | link | parent | on: ASK: How to read user input?

I believe what you're looking to do is assign what's "read" in to a variable e.g.:


(def getUserPrompt ()

    (= msg readline)

    (pr msg)



1 point by mpr 946 days ago | link

Yes, but I'm using the msg arg as the prompt text. Example:

    arc> (= x (prompt "> "))
    > this is the user text
    arc> x
    "this is the user text"
I ended up hacking the ac.scm file to throw away the first newline after an expr is (read). It works for now.


2 points by kinnard 946 days ago | link

I think I understand. You want a function that prints arbitrary user prompts and then takes in user inputs?

You should share your hack!


3 points by mpr 946 days ago | link

Yep, thats the idea. Anyway, here is my hack, in all its hackish glory:

    (define (trash-line c)
      (if (equal? c #\newline)
        (trash-line (read-char))))

    (define (tl2 interactive?)
      (when interactive? (display "arc> "))
      (on-err (lambda (c)
                (set! last-condition* c)
                (parameterize ((current-output-port (current-error-port)))
                  ((error-display-handler) (exn-message c) c)
                (tl2 interactive?))
        (lambda ()
          (let ((expr (read)))

            ;; HACK located here
            (trash-line (read-char)) ; throw away until we hit the newline

            (if (eof-object? expr)
                 (begin (when interactive? (newline))
            (if (eqv? expr ':a)
                (let ((val (arc-eval expr)))
                  (when interactive?
                    (write (ac-denil val))
                  (parameterize ((current-namespace (main-namespace)))
                    (namespace-set-variable-value! '_that val)
                    (namespace-set-variable-value! '_thatexpr expr))
                  (tl2 interactive?)))))))
So I call the trash-line function after the expr is read, but before it is eval'd by arc, so that there is not leading #\newline in the input buffer.

This does seem to work for the readline'ing I was doing yesterday. Probably doesn't handle all cases.

As akkartik mentioned above, this hack is obviated by running scripts in batch mode.


Edit: this change is in my ac.scm file around line 1250


2 points by akkartik 946 days ago | link

I like it! I don't think it'll break anything; can you send a pull request? Then we'll be able to run such code reliably at the repl! That would be sweet.

Edit 38 minutes later: hmm, there's one issue. Right now you can type multiple expressions in on a single line, but this change would drop everything after the end of the first expression. A better approach would be to drop only whitespace and stop at the very first non-whitespace character.


2 points by mpr 946 days ago | link

Thanks! Yeah, I am aware of that bug, and was kind of ignoring it ;) I'll implement your suggested fix then send a pull request.


3 points by mpr 946 days ago | link

Pull request submitted


1 point by kinnard 946 days ago | link | parent | on: ASK: What is Lisp Enlightment?

I now disagree: I realized my cognitive process might actually be the lambda calculus.


Surprised this story got no love. It's providing a powerful new medium/platform for lisping . . . I expect it to have a big impact on the size and character of the lisp community.


1 point by akkartik 947 days ago | link

Seemed like PR:


5 points by kinnard 949 days ago | link | parent | on: Can't access my server

This is a stab in the dark but have you opened the port to receive connections from other "machines". Maybe the firewall is blocking incoming connections.

Also, it might help if you copy exactly your terminal input.

Additionally, the github is another resource though I'm not sure this is an arc issue:


2 points by ca 948 days ago | link

Many thanks for helping with this.

This is what the terminal looks like when I run ./run-news

$ ./run-news rm: cannot remove 'www/news/story/*.tmp': No such file or directory load items: ranking stories. ready to serve port 8080

To quit: arc> (quit)

  (or press ctrl and 'd' at once)
For help on say 'string':

  arc> (help string)
For a list of differences with arc 3.1:

  arc> (incompatibilities)
To run all automatic tests:

  $ hg clone

  $ ./arc

  arc> (load "tests.arc")
If you have questions or get stuck, come to

Arc 3.1 documentation:



4 points by kinnard 948 days ago | link

I believe that error occurs because the news app is attempting to `rm` a temporary dir that hasn't been created yet:

It may be related to what's being discussed here:

But I am able to successfully visit http://localhost:8080/ after running `./run-news`. Alternatively the (nsv) command also works for me.

So I'm not able to reproduce the error that you're getting.

Any luck investigating your firewall?


4 points by ca 945 days ago | link

It's up!

The issue was network (firewall) related. I simply destroyed the firewall (it's on VM so am not concerned about security on this one). On ubuntu that amounted to removing the IPtable rules.

Am looking forward to putting this behind Nginx and seeing how that goes.

Thanks for sticking with me kinnard. It's very much appreciated. Have a great week.


1 point by kinnard 945 days ago | link

Haha, happy to help, would love to see what you're building.

Pay it forward.


Anyone down to develop an arc scripting language for VR?


1 point by kinnard 950 days ago | link | parent | on: Why Lisp?

Analysis of homoiconicity by comparing S-expressions, json, and xml is pretty compelling compared to all the other lisp evangelism I've read.


This sounds like stack based LISP as opposed to "list" based "LIS"P


2 points by akkartik 949 days ago | link

Yes, my impression is that "stack-based lisp" describes to a 't'. In Factor you can throw code on the stack by a process called.. quoting. And then invoke it inside some other higher-order function.