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June 24

Array deconstrctors in Javascript ES6

In Javascript ES6, we can use array deconstrctors like so:

   > [key, value] = [1,2];
   [ 1, 2 ]

But using it in a lambda function doesn't seem to work:

   > const foobar = [[1,2],[3,4]];
   undefined
   > foobar.map((key, value) => console.log(key));
   [ 1, 2 ]
   [ 3, 4 ]
   [ undefined, undefined ]
   // Wrong results
   > foobar.map([key, value] => console.log(key));
   ... 
   ... 
   // Syntax error

Is there a way of getting it to work? Scala Cats (talk) 20:42, 24 June 2017 (UTC)[reply]

Security problems with weak wifi connection

At home, I have a router for my secured wireless network, and everything consistently works fine inside the apartment. Occasionally, I'll have reason to try to use it while sitting in my car outside, where I'm on the limit of its range; it tends to alternate between working-but-really-weak and not working at all. No surprise.

When I try to load a webpage and the network's too weak to work, the browser (latest IE) normally loads a "can't load this page" message, as I'd expect. However, occasionally it instead gives me a sort of security warning. Here's the most recent one:

Can’t connect securely to this page This might be because the site uses outdated or unsafe TLS security settings. If this keeps happening, try contacting the website’s owner.

This came when trying to load https://en.wikipedia.org/wiki/Donjon. Why would it claim a security problem instead of just saying that it couldn't load the page? Does a secure site require some sort of stronger connection than the absolute minimum, i.e. it's possible for the connection to be working while yet too weak to authenticate? Or perhaps the network was so weak that the router couldn't realise that the computer was properly connected to it? As I note above, this problem only arises when I'm on the edge of range, and nothing is wrong; I'm just curious. Nyttend (talk) 23:13, 24 June 2017 (UTC)[reply]

This would happen when the browser connects to the web site, but the initial security negotiation did not complete. So a failure during the TCP session. It probably timed out in the session or lost wifi connection during this phase. Another way to fail is if it tries to check the certificate and gets an error or failure connecting to the certificate authority. Graeme Bartlett (talk) 00:40, 25 June 2017 (UTC)[reply]

SD cards with secure elements

I found out about this kind of SD card (usually in a microSD form factor) a few months ago and I'd like to try one out. They seem to be like these new SIM cards that also have secure elements usable for NFC-related stuff, but I don't have a phone that uses SIM cards and I'd prefer an SD card because that way I'd have an easier time interacting with it on a general-purpose computer. Does anyone know where to find programmable ones, i.e., the kind that have not yet been programmed with an OEM's public keys and security settings? — Melab±1 ☎ 23:58, 24 June 2017 (UTC)[reply]