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Comment Tax and Currency Value (Score 1) 156

If an economy goes bad enough (e.g.hyperinflation) black markets spring up, and only at the end are the cognac/cigarettes exchanged for the currency to pay the taxes. So being accepted for tax isn't a sufficient condition for a currency to have value.

In a normal economy, currency has value because it's accepted everywhere for local transactions because of certain safeguards*. That is, if I hand over money to a store to buy something, and the storekeeper never hands me my item, I can go and ask Plod for help. And the converse situation holds as well. In a black market, you have to rely on word of mouth (or force) to put the unscrupulous out of business.

(* The flip side is, as Libertarians are fond of pointing out, is the currency can be manipulated. That's the price you pay for having the state involved in maintaining the Rule of Law.)

Comment That's a comforting notion... (Score 1) 158

But the mindset that lead to the poor code being produced in the first place will also be unable see that the solution is to bring in a professional to do it right.

Non coders only see the physical component of coding and can't see anything else; just as if I watch a carpenter work, I won't recognise the skills applied there. Applied to management, they don't know that they don't know, and therefore use the only criteria they understand, which is price.

Comment Uncertainty Principle (Score 1) 224

If I understand correctly, you are actually only certain of position or momentum when the wave function collapses to point values. i.e. You are HERE or you are going EXACTLY this fast.

When you perform a measurement (say of position), the wave function will indeed say: The probability of finding the particle at 'x' is 1. However, the more certain you are of it's position, the less certain you are of it's momentum because of the relation dPdM ~ h_. (Where d is the uncertainty in the measurement; h_ is Planck's Constant). You are correct in that it's the wave function that is spread out, not the particle itself. If you measure the particle's position again a little later, there's no guarantee you'll find it again at 'x'.

P.S. I've not studied physics formally, but I've found this series from Yale to be quite instructive and easy to follow. I might have misunderstood, so I welcome any corrections from actual physicists.

Comment Toy Example (Score 3, Interesting) 186

I'm trying not be as automatically dismissive as others, but this example isn't convincing. If your enterprise can be encapsulated by eleven use cases, any framework will suffice. But even in this toy example, we can some obvious missing things.

For example, the "Purchase Order" entity includes a reference to a sales rep. From it's inclusion we infer that is important data, so it would also need to be added as a "reaction". There's also no hint on how these "reactions" are actually implemented. The original article claims that consistency is enforced but doesn't really explain why.

The customer.balance Rx, specified for the place order use case, states that its value is the sum of the unpaid order totals. This expression is automatically reused over all transactions that use the field. So, the balance is increased if an order is added, decreased when it is deleted or paid, increased when you raise the quantity, and so forth. With imperative code, it is easy to overlook one of the use cases introducing âcorner caseâ(TM) design and coding errors. Reactive practically eliminates this class of error.

The above might be what they mean, but that's not sufficient for consistency. If your database field is merely a duplicate of derived data in other entities, you shouldn't pat yourself on the back for avoiding a problem you created in the first place! You can also overlook a use case in the analysis phase too, and then you'll fail to include it regardless of the framework.

I think I'd like to see an example with all the entities included and some normalisation. Then maybe I might be convinced that RP has any advantages over triggers.

Comment Re:databases (Score 5, Interesting) 598

Surely any programmer ought to know the underlying principles that make databases work (ie ACID etc) even if they never intend to go anywhere near multi threading. Even in single threaded programs knowing what and how ACID works can help. Have you never done a write() and wondered where the data you sent to disk went?

Perhaps the relational calculus might not be strictly necessary, however if knowing the theory behind relations helps engineers from naively treating databases as data garbage dumps, it'd be worth it.

Comment I don't miss Middle-Click Paste on OSX (Score 1) 729

It's strange. Before I switched to OSX, I used it all the time in FVWM and found it so useful I even bought a proper 3 button mouse (ie three parallel buttons, none of this scroll-wheel malarky). I wonder if the environments are just too different. That the resulting workflow changed so much that middle-click-paste would've been unnatural.

On the other hand, maybe t's been so long that I've accepted the fact, so I no longer think "that operation would've been so much easier in X)

Comment Maybe trying to determine demand? (Score 1) 112

In marketing, you're apparently supposed to determine how much of a market exists for your product (ie will anyone buy it) before you start designing and building. Something I wish I'd learnt before I built my app, but there's always next time.

In the case of this app, the point might be market research instead of raising capital. And now it's on slashdot, it looks like they're getting a two-fer.

Comment I hate Watermelons as much as the next Capitalist (Score 2) 236

Truth Quark was just examining one of the arguments between inaction and action in a logical way. Put explicitly, climate change is a sufficient condition for reducing emissions, but not a necessary one. If an Oracle appeared and told you climate change was definitely not happening, would you stop trying to reduce pollution?

Slashdot likes car analogies, so here's one: When your mechanic says he can't find a problem, it doesn't necessarily mean your car is fine.

Comment Become a Free Software Manager (Score 2) 321

Determine if there's sufficient demand for your preferred environment to grow and be maintained, sufficient to pay the salaries for a small dedicated team. If you can't code, perhaps you can manage the project or handle the marketing. If the demand isn't there, you may have to deal with the situation as is, or transition to another platform.

Comment Re:iOS apps on a Mac? Why? (Score 1) 512

I've seen a few apps which have both desktop and mobile versions. I can't name them offhand because I didn't expect this question. I think they were primarily "productivity apps" like spreadsheets, where you can expect to spend a bit of time in. I think the reason it's not more common is iCloud integration. It's not difficult to implement, but does require additional effort in the form of design and most especially testing. I suspect that most developers don't think the effort is worth it. I considered adding it to my app, but when I looked at all the apps I use regularly, none of them include iCloud integration.

I haven't ported my app to OS X, but the base would be easy enough. I'd have to be sure of demand before spending the time and money. I'm sure that's true of any IOS developer of apps that don't require specific hardware.

Comment Re:Backups (Score 1) 192

> Should the crowd here really be supporting marketers? I think we are enlightened enough to see how much they cost our society with a very poor cost to benefit ratio compared to other economic endeavors

I used to hold that view, but it occurred to me that might be slightly irrational. If you have a product or idea you need to A) know if anyone will buy it B) let people know it exists. Kickstarter is obviously a marketing endeavour, and it seems to be of benefit.

On the other hand, "The Greatest Movie Ever Sold" talks about a South American town which banned advertising. The store owners relied on word of mouth for their business. I'm not sure that would work for a business with only an online presence. Few things go viral, and nobody's entirely sure why one thing goes viral and the other not. Waiting for people to patronise your business is about as effective is waiting for the phone to call in starting a relationship.

And to return to the subject, it reminds me I need to make a backup of my hosted site Real Soon Now.

Comment Future Options (Score 1) 131

It might be nice to have a mature "wine like" option for OS X. Eventually, your perfectly functioning, useful computer is going to be "too old" to install the latest OS. Sometimes that just feels like forced obsolescence so having an alternative option in this case is useful. Also, if this was available around the time Apple abandoned the XServe customers, it might have eased their transition a little.

Witness all the grumbling about Apple in the "Larry says Apple is doomed" thread. If Apple goes off the rails, having the option of switching to Linux whilst still accessing your programs and data would be handy.

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