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ac42

111 karma · joined February 17, 2019

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ac42··on Leaf-cutter ants have rocky crystal armor, never before seen in insects
higher intelligence = higher ignorance?
ac42··on hCaptcha now runs on fifteen percent of the internet
Just tried the demo and found it somewhat confusing

"enter your name and your favourite vegetable" is to lure bots into responding?

When "I am human", I am asked to select boats and fail because I didn't tick the images with ships.

I would not like to add a Captcha that appears to be smart Alec, has a tendency to trigger the same in the respondents or, worse, makes customers feel stupid. reCaptcha somehow seems better at avoiding this.

ac42··on World's first no-kill eggs go on sale in Berlin (2018)
Why would the egg contract in the first place?

It's more likely that the "applied pressure" is simply negative...

ac42··on Metal monolith found by helicopter crew in Utah desert
Indeed, and to my feeble defense:

> The book was credited to Clarke alone.

TIL :)

ac42··on Metal monolith found by helicopter crew in Utah desert
Clarke.

https://en.m.wikipedia.org/wiki/Arthur_C._Clarke

ac42··on Booting from a vinyl record
Ouch!
ac42··on The Most Common Errors in Undergraduate Mathematics (2009)
At the least, you're not alone.
ac42··on The rise of platonic co-parenting
https://news.ycombinator.com/item?id=24962121
ac42··on Photos from inside a Typhoon class submarine
They used cats specifically for their inbuilt probability amplification properties.
ac42··on Ask HN: What are some good methods to prove current time?
Make it known at the time (possibly via something likely strongly dependent like a hash or encryption). If it is not observable, it may just as well not have happened. Call it quantum mechanics or simply common sense.
ac42··on I Lived Through Collapse. America Is Already There
/s
ac42··on Dual-flush toilets 'wasting more water than they save'
This just saved my day :-)
ac42··on Security by obscurity is underrated
Passwords / keys are obscure by definition. With this in mind, "Security by Obscurity" technically adds one or two bits to your key.
ac42··on Git-Based Wiki
Gitlab has this for a while already https://docs.gitlab.com/ee/user/project/wiki/
ac42··on Ride through Wuppertal on ‘the flying train’ in clear footage from 1902
According to WP, what led to this picture is photo editing.
ac42··on “Cold Tube” cooling system uses half the energy of an air conditioner
The WP article points out the issue of condensation, which the OP claims as being addressed in a novel way.
ac42··on New ‘Meow’ attack has deleted almost 4k unsecured databases
1) This is not the "real world".

2) Even if it were, and my twenty-something assistant left my shop door open at night consistently, to me, the question of the legality of the resulting damage would be rather secondary.

ac42··on Ask HN: What’s a big trend we should all be following?
Using one's own head to draw conclusions.
ac42··on RLCD, better technology than E-Ink itself?
http://www.einkmonitor.com/
ac42··on 25 Years of PHP
Hack is interesting and the native C++ interface is a breeze. But choose PHP if you want to live. Hack has only a fraction of the PHP ecosystem and if you mix with PHP, then you lose the advantages very quickly.
ac42··on Tinkerbell Effect
https://en.m.wikipedia.org/wiki/Subjectivism
ac42··on Man built a bunker under Hampstead Heath and lived in it for two years
You are not and if it makes you feel uncomfortable, this may put you back on track http://z80.info/zip/z80cpu_um.pdf
ac42··on 500 Byte Images: The Haiku Vector Icon Format (2016)
> Now we just need a file format that combines all this. :)

TTF?

ac42··on Shit – An implementation of Git using POSIX shell
I wasn't aware of the plumbing / porcelain metaphor in git until now.

It's fantastic to what lengths some of us go for a good pun :-)

ac42··on Is there a regular expression to detect a valid regular expression?
:-)
ac42··on Is there a regular expression to detect a valid regular expression?
Not sure if you are trolling, but here we go...

In the case at hand, correctness of the validator expression V clearly means "V determines well-formedness of any regular expressions" which is clearly not implied by "V is well-formed" (a much weaker statement because ".*" is well-formed but matches everything). Therefore, when applying V to itself, we only learn if a weak requirement for V's correctness holds.

Similar, perhaps, to validating whether a given number is a Gödel number of a well-formed logical statement rather than assessing the verity of the logical statement it encodes.

Also, I am not saying whether it is or is not possible to build such a regular expression. Rather, the question just doesn't tick the boxes of either, the Liar's Paradox, nor Gödel's Incompleteness result -- contrary to what was suggested. So you could still be right but for different reasons.

ac42··on Is there a regular expression to detect a valid regular expression?
Free of English errors. Not semantic errors. We don't even know it's a "liar".
ac42··on Is there a regular expression to detect a valid regular expression?
The "liar" only says "I can proofread Essays" and not "I am lying".
ac42··on Is there a regular expression to detect a valid regular expression?
https://en.m.wikipedia.org/wiki/Nondeterministic_finite_auto...
ac42··on Is there a regular expression to detect a valid regular expression?
IIRC, regex can be implemented by an NFA which can't solve balanced parentheses that are part of regex syntax.
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