kragen

I think you can, in theory, break apart stable lead nuclei by spallation, transmuting some of them into somewhat lighter elements (first-row platinum-group elements, tungsten, that kind of thing), which you can fairly easily separate by chemical means, then bombard with neutrons and alpha particles until some of them become gold, go through another chemical separation step, and repeat. You need energy input for all of this, but I don't think you need to deal with significant quantities of antimatter, just the occasional positron emission.

I admit I don't know much about nuclear reactions, so please let me know if I'm talking nonsense here.

I agree that Central European capacity factors for solar are pretty bad, and that heat pumps are still economical in more polar countries, and will remain so for a few more years.

I'll answer the rest of your extremely interesting comment later, as I'm being drawn away at the moment, but I want you to know that I appreciate it very much.

As I explained 5 comments up this thread, people are going to stop picking those "better" options because they're no longer economical. I think you just didn't notice that part of my argument, because you never responded to it.

Also, I don't think it's accurate to describe electrical resistance heating as "the thermodynamically worst heating technology possible". Electrical resistance heating is generally close to 100% efficient. It's actually thermodynamically possible to make heaters that are less than 100% efficient; MacKay explains, for example, that he heats his house with a 90%-efficient condensing boiler, and it's common for fireplaces to be around 20% efficient, because most of the heat goes up the chimney instead of heating your house.

Fireplaces are actually thermodynamically possible machines. I understand that you've never seen one, but I assure you that they do exist.

I've actually lived in houses where the fireplace had negative efficiency at times, sucking more heat out of the house (in the form of warm air) than they added back in the form of radiation.

That "absolute worst case" happens in my house most of the winter, and it's common throughout the rich world. The only place it isn't common is where people don't have electricity yet. Even in Brazil, where nobody needs a space heater, electric water heaters are common.

When that absolute worst case is happening in the house's living space, we can and do "convert" heat to electrical energy savings 1:1, because every joule "wasted" by cooking food with gas, or heating the house with a corn stove, or warming up the floor with sunlight for passive solar gain, is another joule earlier that the space heater's thermostat will turn it off.

We're going to need more than grid-scale batteries to electrify trucks, ships, and long-distance airplanes. PaulDavisThe1st is right about that! Solar-powered fuel production from CO₂ is one possibility.

"Overproduction" is nonsense, and solar panel prices have been continuously dropping dramatically for 50 years now; they're not likely to stop anytime soon.

Current solar panel production is only about a terawatt per year, which would take about 80 years to merely replace all of global marketed energy consumption (≈20TW, but those are not peak watts), and 90,000 years to reach Kardashev Type 1, where total solar power capture is roughly equal to the amount reaching the Earth. So current solar panel production is too low by roughly a factor of 1000.

We're very far from overproduction of solar panels. What we have is underconsumption of solar panels. But that has been improving dramatically year by year, and will probably continue to improve.

Yes, there is currently a shakeout where lots of solar companies are likely to go bust. That's what happens in industries that are growing rapidly: you have to place big bets to stay in the game, and sometimes you fuck it up and your company blows up. It's been happening for 20 years already — the article you linked mentions three big shakeout cycles that I remember, and I think there have been others I just wasn't paying attention to.

Speaking of not paying attention, if you think "it's really never been a better time to buy panels than now", you clearly haven't been watching module prices, even though I linked the historical data in the comment you are replying to, and I even quoted some prices. Prices are up 20–30% since the beginning of this year, and since November (€0.065/Wp low-cost, €0.100/Wp mainstream, €0.130/Wp high efficiency) they're up by 30–40%.

There had never been a better time to buy solar panels than last November. That's the usual situation with technological progress, actually: there has never been a better time to buy a thing than right now, and if you wait another month, it will get even cheaper. Last year, prices were mostly flat; November was the low for low-cost modules and high-efficiency modules, while mainstream panels were actually 5% higher than their low, which they had first hit in November 02024. But, still, high-efficiency panels hit record lows last year in January, August, September, and November, while low-cost panels hit record lows in July and November. The year before was one of vertiginous price declines: high-efficiency panels hit record lows in January, February, March, May, July, August, September, October, and November; mainstream panels hit record lows in January, March, June, September, and November; and low-cost panels hit record lows in January, April, August, October, and November.

This followed a three-year gradual rise in prices starting in late 02020, but we also saw record-low monthly prices in most months of 02020, most months of 02019, and all months of 02018.

In any of those months, you could have correctly said, "it's really never been a better time to buy panels than now," even though an even better time was coming up, in most cases, a month or two later. Prices have shot up this year, just like they did in 02020–02022, but within three or four years at most, they'll be lower again. Swanson's Law https://en.wikipedia.org/wiki/Swanson%27s_law remains in operation, and on the Wikipedia page you can find a nice graph from 01975 to 02024.

You said, "combine this with the global backing-off of the Paris Agreement (and subsequent subsidy defunding) and power utilities in the US abandoning clean energy goals in order to immediately increase output for proposed hyperscale facilities and you've got something of an enduring demand shortage", but this is nonsense reasoning, because you've buried a false premise: you think that solar panels are a more expensive way to generate energy than fossil fuels, which is wrong.

In fact, as should have been immediately obvious from the prices I already quoted in the comment you were responding to, solar panels are now enormously cheaper than thermal power plants, even before you add in the cost of the fuel. The proposed hyperscale datacenter facilities are precisely where the demand for today's ultra-cheap solar energy is going to come from — people in the US are spinning up portable gas turbine generators to power their data centers for regulatory reasons, but that's a desperate stopgap, not a long-term solution.

Energy is one of the largest cost items for any datacenter, so ultimately nobody can run a competitive datacenter on fossil fuels, not when they're competing against solar.

Usually it's fundamentally worth less, but not a specific amount less, the way Jamaican dollars and lead are. And, if you're using resistive heating, they're worth exactly the same amount.

You're right, and I appreciate the correction — even Norway mostly runs its transport on fossil fuels, not electricity, and trucking and ships aren't going to be electrifiable in the short term. Here in Argentina, when we ran our grid mostly on hydroelectric, the cars were still running mostly on gasoline and compressed natural gas.

(Yes, I know that makes me sound like an LLM.)

That's true! What was holding up EVs 18 years ago, or for that matter 18000 years ago, was not physics, but the humans' ability to efficiently make things such as batteries and high-efficiency electric motors.

Chapter 21 of draft 2.9.3 from 02008 https://web.archive.org/web/20080906132444/http://www.infere... begins:

> In the last chapter, we learned that electrification could shrink transport’s energy consumption to one fifth of its current levels; and that public transport and cycling can be about 40 times more energy-efficient than car-driving. How about heating? What sort of energy-savings can technology or lifestyle-change offer?

and it goes on to talk about heat pumps, as today. So I think that even versions from 02008 got this right, though evidently that was at least the 13th numbered draft.

If I'm interpreting you correctly, you're saying that my original disagreement was mostly with my misunderstanding of what you meant, and the only thing we actually disagree on is how likely it was that Wirth knew Alan Kay personally, which neither of us is very sure about?

A lot of companies started in 02002 based on spreadsheets of available data went bankrupt due to the available data being wrong, or due to things not included in the available data at all. A quick check of Wikipedia turns up:

- https://en.wikipedia.org/wiki/MStar (patent infringement, the remains bought by MediaTek)

- https://en.wikipedia.org/wiki/Green_Flash_Brewing_Company (succumbed to competition from local craft breweries, lender foreclosed, the remains bought by private equity)

- https://en.wikipedia.org/wiki/Primaris_Airlines (bankrupt in 02008, unclear why)

And those are cherry-picked from companies that got big enough to be "notable" by Wikipedia's guidelines. Far more companies never reach that level.

The conservative estimate is that any time someone tries to deploy a new technology, it will fail. Most innovations (new technologies or companies) do.

Take a look at the HN front page from 10 years ago: https://news.ycombinator.com/front?day=2016-09-28 There we see Uber's self-driving truck initiative Otto (an acquisition), deep learning startup Skymind, a new static Linux distro called Stali, and a bunch of things that weren't innovations. All three of those things failed; Stali hasn't been updated since 02019. LuaTeX, Coinbase, Linux, Wikipedia, and dyeing with indigo are other innovations that feature on that page, but they were already very old.

I never got a blanket claim of "actually renewables can't work alone" from the book. It seemed more like "actually you need to understand things quantitatively or you are doomed to talk nonsense".

MacKay's "renewables can't work alone" claim always seemed carefully scoped to the economics of 02008 (when solar modules cost 33× as much as they do now) and also his own densely populated, rather polar country. Renewables were already working nearly alone, at scale, in equatorial countries and more sparsely populated countries; I live in Argentina, whose grid was mostly hydroelectric at the time, and next door to Brazil, where a large fraction of the automotive fleet ran on sugar-cane-derived ethanol, which is a viable renewable energy source (unlike, apparently, corn ethanol).

Thermal energy and electrical energy really are the same thing, not two different quantities that happen to be measured in the same units, like grams of lead and grams of gold, or your example of US dollars and Jamaican dollars. When you convert less than half of the chemical energy in the gasoline into mechanical work to move the car, the other 50+% of the energy is converted into heat. Carnot gives us a reversible conversion factor between them, but it depends on the combustion temperature rather than being some kind of constant, as in your Jamaican-dollar example.

Technically you can interconvert grams of lead and grams of gold one to one, too, but interconverting electrical and thermal energy is so easy that it happens all the time unintentionally.

MacKay does in fact cover the Carnot factor you're talking about; his Chapter 21 http://www.withouthotair.com/c21/page_140.shtml begins:

> In the last chapter, we learned that electrification could shrink transport’s energy consumption to one fifth of its current levels; and that public trans- port and cycling can be about 40 times more energy-efficient than car- driving. How about heating? What sort of energy-savings can technology or lifestyle-change offer?

And then he goes into not just household heat pumps, and their achievable coefficients of performance, but also municipal combined heat and power, which take that ≈50% of the chemical energy "lost" from thermal power plants as waste heat and pumps it into your house.

So, far from being ignorant of the issue as you seem to be implying, he presents a more complete picture of the issues than you are presenting.

Specifically for household climate control, I suspect that both heat pumps and CHP are much less relevant now that we have cheap solar. You can think of a heat pump as a way to reduce the amount of solar-panel area that you need to heat your house. The trouble is that solar panels cost €0.13 per peak watt, while heat pumps cost closer to €1 per peak watt, so it may be cheaper to "waste" energy on heating your house resistively with a nichrome wire than to use a carefully engineered heat pump.

> His forecasts of the impact of solar and wind is based on prices and performance from 2008. Prices have come down an order of magnitude since then

This is going to sound like one-upmanship or nitpicking, but I think it's important to know that this understates the change. https://web.archive.org/web/20100722072720/http://www.solars... says that in May 02009, crystalline solar cells in China cost €2.17 per peak watt, a decline of 26.4% from January 02009, whose price is not listed directly but which we can calculate as €2.95 per peak watt. If the price had declined by only an order of magnitude since January 02009, it would now be €0.295 per peak watt.

But, according to https://www.in2013dollars.com/europe/inflation/2009?amount=1..., "€100 in 2009 is worth €145.57 today." So, if we adjust for inflation — as we should — if the real price had declined by only an order of magnitude since January 02009, it would now be €0.429 per peak watt.

In fact, today, "mainstream" solar modules are currently €0.130 per peak watt, according to https://www.solarserver.de/photovoltaik-preis-pv-modul-preis..., and those are Chinese monocrystalline modules.

So the price of solar modules now is actually 3.3 times lower than what a careful reader would infer from your remark. Solar module prices have declined since January 02009 by not merely an order of magnitude but 33×. That's slightly closer to two orders of magnitude than to the single order of magnitude you said. Now they are at 3% of the price they were at when MacKay wrote his excellent book.

(Which does, as others have pointed out, explain the efficiency advantage of heat pumps.)

I think the main objective of both the Lilith workstation and the Oberon language were to be practical tools for the kind of graphical user interfaces Kay proposed in his dissertation in 01969 and dedicated much of his PARC research group's effort to advancing. As explained above, Kay's influence is generally acknowledged to be the reason that the PARC's Xerox Alto was capable of running such graphical user interfaces at all.

Oberon's procedure-typed fields came from Modula-2†, and I believe that specifically the reason that Modula-2 reintroduced the procedure (function pointer) types that Modula‡ had removed from Pascal was to support the kind of GUI programming that Wirth had been exposed to during his PARC sabbatical in the Mesa group. However, all I have to support that belief is the chronology, the fact that Oberon does in fact use them for that (and, as far as I've seen, only for that), and some vague memories of reading Project Oberon last millennium.

Pascal procedure types could only be passed as subroutine parameters, which enables the use of nested subroutines as closures without risking runtime errors or requiring garbage collection, because the referenced procedure cannot be called after its lexically-enclosing parent has returned. Modula-2 procedure types do not have this restriction, so they can be stored in records; instead, they have the restriction that, like C function pointers, they cannot refer to nested subroutines.

So I think that Smalltalk's (and Kay's) influence on Oberon was very strong indeed, but mediated through influence on the Mesa group. Certainly Kay's flamboyant and dynamically-typed style, emphasizing recovering from errors rather than preventing them, was not to Wirth's liking.

______

† https://www.research-collection.ethz.ch/bitstreams/289cc859-...

‡ https://scispace.com/pdf/modula-a-language-for-modular-multi...

You could be right that Wirth didn't know Kay well enough to recognize him. I thought of PARC in that period as being relatively small, and Kay was fairly prominent within it, so I'm sure he had at least seen the man.

However, I don't think it's particularly adventurous to claim that the Mesa group's GUI was inspired by Smalltalk's, though. They added their own innovations, of course, like the tiled-viewer approach Wirth later used in Oberon, but the basic grammar of windows with titlebars and text in them, noun-verb commands acting on highlighted text selections, scrollbars, menus, and a mouse to point at them, was developed in Smalltalk from its Augment/NLS roots.

Brad Allan Myers wrote his 01980 MIT master's thesis, "Displaying Data Structures for Interactive Debugging"†, about the graphical debugger Incense, which he wrote in Mesa, initially while he was at PARC. By chance this is one of the earliest papers describing the GUIs written in Mesa. What he says about Smalltalk's contribution to GUIs is:

> It was felt that graphics would make the system easier to learn and use [Kay 77]. Smalltalk developed the idea, first proposed in the FLEX system [Kay 69], of using multiple overlapping rectangular regions called windows to extend the available screen space [Goldberg 79]. [...] Smalltalk presents a uniform window interface both to the programs and the user, thereby allowing complex systems to be easy to use (e.g., an animation system [Backer 76] and Thinglab (section 3.6.4)).

"Backer 76" is presumably Ron Baecker's SIGGRAPH paper "A Conversational Extensible System for the Animation of Shaded Images," because there's no "Backer" in his bibliography. Thinglab is the constraint satisfaction system that Alan Borning wrote his 01979 doctoral dissertation on. Goldberg is of course Adele Goldberg from Kay's Learning Research Group."Kay 69" is Alan Kay's doctoral dissertation, "The Reactive Engine".

He credits pointing devices to Sketchpad in 01963, pointing for interactive debugging to someone named Zimmerman in 01967, and the mouse to Bill English in 01967. He shows a screenshot of Teitelman's DLISP UI for debugging Interlisp, which evidently also has highlighted text selections, menus, and overlapping windows with titlebars; Myers describes its windows as "essentially the same as Smalltalk windows", not vice versa.

With respect to the Alto, on p.37, Myers calls out the importance of the Alto's BitBlt microcode for GUIs like the one he mentions; he doesn't mention that it originated in a non-microcoded version written in 01975 by Dan Ingalls, Larry Tesler, Bob Sproull, and Diana Merry, for Smalltalk-72, and that the microcode version was written by Ingalls. At least Ingalls and Merry were in the LRG; I'm not sure about Tesler and Sproull.

On p. 39, we see a screenshot of Mesa's normal windowed debugger, which used overlapping windows at the time — so Cedar's tiled viewers were a later innovation, even within the Mesa group. The windows have titlebars and what appears to be a Smalltalk-style vertical popup menu.

None of the screenshots show scrollbars, but even in Smalltalk they were pop-up at the time to save scarce screen space.

The reason I keep mentioning titlebars and popup menus is that precursor GUI systems like SKETCHPAD, GENESYS, and Augment/NLS didn't have them. They all had pointing devices and windows, and GENESYS even had menus, but not popup menus.

You might reasonably argue that GUIs that ran on the Alto had to use a mouse like Smalltalk did, not because they were modeled on Smalltalk, because that's what the Alto had. But why did the Alto have the mouse? I don't know which ideas were contributed by which contributors, of course. But Kay was one of those contributors.

Shortly before Myers's thesis, in 01979, PARC CSL-79-11, "Alto: A Personal Computer"‡, which lists Lampson but not Kay among its authors, begins its "Acknowledgements" section by saying, "The concept and structure of the Alto are due primarily to Chuck Thacker, Ed McCreight, Butler Lampson, and Alan Kay."

Let's check out Teitelman's 01977 paper about DLISP, "A Display Oriented Programmer's Assistant", PARC CSL-77-3. Fortunately he published it later in the International Journal of Man-Machine Studies§. What does Teitelman say? Where does he assign the credit for the GUI idioms he used in DLISP?

> The idea of a display composed of multiple, overlapping regions called "windows" is attributable to and an essential part of the Smalltalk programming system designed and implemented by the Learning Research Group at Xerox Research Center (1976). In particular, much of the way that windows are used in the system described here was influenced by the work of Dan Ingalis on the Smalltalk user interface. The idea of using the display as a means for allowing the user to retain comprehension of complex program environments, and to monitor several simultaneous tasks, can be found in the work of Dan Swinehart (1974). The use of the "mouse" as a pointing device for selecting portions of a display goes back to the early work on NLS (English, Engelbert & Berman, 1967).

Teitelman was also the main author of Cedar.

How about Lampson, who led Mesa and Cedar? Where did he think the GUI ideas came from? In 01988° he says:

> Yet another ARPA project that had a strong influence on the Alto was Alan Kay's Flex machine, also called the Reactive Engine [21]. [...] Like Engelbart, he attached great importance to a high-quality, rapidly-changing display. He later coined the name "Dynabook" for the tool he envisioned, to capture its dynamic quality, its ubiquity, and its comfortable fit with people [22]. [...]

> The electronic office and the Dynabook, then, were the two threads that led to the Alto system. [...]

> The outstanding exception to these observations is the Smalltalk system, which was built by a tightly knit group that spent a lot of effort developing a consistent style, both for programming and for the user interface. Smalltalk also has a software-implemented virtual memory scheme that considerably relaxes the storage limitations of the Alto. The result is a far more coherent and well-integrated world than can be found in the rest of the Alto system, to the point that several of the Alto's successors modelled their user interfaces on Smalltalk. The price paid for this success was that many Smalltalk applications are too slow [...]

> The Alto system was built by two groups at PARC: the Computer Science Laboratory (CSL), run by Robert Taylor and Jerome Elkind, and the Learning Research Group (LRG), run by Alan Kay. LRG built Smalltalk, and CSL built the hardware and the rest of the system [...]

> Figures 1-3 are typical screen arrangements from three systems. Smalltalk (Fig. 1)' uses overlapping windows without icons, and the position of a window is independent of its function (unless the user manually arranges the windows according to some rule). Smalltalk was the first system to use overlapping windows and pop-up menus. The Bravo editor (Fig. 2) uses one column of tiled windows, with a control window at the top, a message window at the bottom, and a main window for each document being edited, which may be subdivided to look at different parts. Cedar (Fig. 3) uses two tiled columns and rows of icons at the bottom (which can be covered up). This window system is called Viewers; much of its design was derived from Star. The top line or two of a window is a menu. Cedar also allows the entire screen image, called a desktop, to be saved away and replaced by another one; this is switching on a large scale. Markup has a pop-up menu scheme like Smalltalk's, but considerably more elaborate (Fig. 4).

So, in conclusion, I think that my claim that Mesa's GUI was inspired by Smalltalk, far from being adventurous, is on solid ground.

______

† https://dspace.mit.edu/bitstreams/b8c2f945-251d-4ff2-8baa-82...

‡ https://archive.computerhistory.org/resources/access/text/20...

§ https://doi.org/10.1016/S0020-7373(79)80015-2

° https://dl.acm.org/doi/abs/10.1145/61975.66921 or http://bwl-website.s3.amazonaws.com/38-AltoSoftware/WebPage....

I could be wrong, but I think he wrote Treesheets before he was "in the games industry" (but after he wrote Cube!).

While I agree with what you say about Oberon and Smalltalk, you've made some mistakes about Wirth.

Wirth did know Kay; his inspiration for the Lilith and Oberon projects, as he explains in his HOPL III paper on Modula-2 and Oberon, was spending a sabbatical year at PARC in 01976 and 01977, where Kay was then the director of the Learning Research Group, which had pioneered the GUI. However, Wirth's style was more influenced by the Smalltalk-inspired GUI being written in Mesa, which would officially give rise to Cedar in 01980. As he explains in the Oberon book, he considered overlapping windows (which Smalltalk-76 had) to be unnecessary complexity.

Smalltalk-76 already had compiled virtual methods and table-based polymorphic dispatch like SIMULA, by the way.

If I recall correctly, he invented the optimal way to do it and published it in the original paper: use an arbitrarily long random code. The difficulty is that decoding a random code in the obvious way (compare the received codeword against each codeword in the codebook and decode as the one with the lowest Hamming distance) requires an exponentially large amount of both memory and computation. As I understand it, the advances since then have all been about how to get closer to the Shannon limit with reasonable amounts of computation by using codewords that aren't truly random.

Currently the title says "Web-based IBM 1620 emulator and IPL-V from 1963" until HN's title policy inevitably vandalizes it to remove the informative part. But, to give further context on IPL-V, IPL (I think actually IPL-IV) was key to some early AI research, but the main reason it's interesting in 02026 is that it's what inspired Lisp. It's a terrible programming language by today's standards, and the manual is a horrible slog, but you can see the seed of almost every programming language popular today in it.

This is an awed biography of Fabrice Bellard. Unfortunately there's a strong smell of AI prose around the article, but the content seems good.

Well, of course, getty doesn't know whether the thing plugged into the serial port is a teletype or a CRT terminal. But the actual Sun console isn't a serial port!

KILL isn't Ctrl-C. That's INTR, as you can verify in stty -a. KILL is Ctrl-U.

> My first exposure to Solaris was in 2003 when Linux had Gnome 2.6 and Solaris had CDE. The UI on my Debian box seemed decades ahead of the Solaris machines I managed, which looked like Windows 3.1 and performed about as well.

Linux having better UI than proprietary Unices (except SGI) was true from the beginning. In 01993, even before package managers, the Linux standard was color rxvt, color ls, Seyon, fvwm with multiple virtual desktops (really important at 800×600), Emacs preinstalled, and you could termify your web browser and whatnot so you could run them at home on a dialup shell account. Proprietary Unices (except SGI) had monochrome xterm, vi (with no arrow key support), and typically either twm or mwm, which both looked like shit and still do. Suns sometimes had olwm but Sun had sort of abandoned Open Look by that point. If you had a Sun at home connected through a dialup shell account, you could forget about running any TCP/IP apps on your Sun. By 01996 the Linux world had slirp, so you didn't even have to termify your TCP/IP apps, while Solaris didn't even include a C compiler anymore.

CDE seems like somebody thought that the problem with Motif was that, although it was butt-ugly, it wasn't quite ugly enough.

And, yeah, backspace worked. Also automatic window resizing. And for years Solaris had a totally fatal TCP round-trip estimation bug which made TCP connections to Solaris machines over dialup incredibly slow. Linux was just dramatically more technically competent.

Sun did have a pretty amazing engineering culture. They shipped SPARC, Open Look, NeWS, Java, HotJava, HotSpot, NFS, Sun RPC, yp/NIS, Spring, ZFS, OpenBoot/Open Firmware, and I think even Sprite, and for a while they employed the Tcl team, bringing Tcl out of the stone age. But they sucked at fixing the fatal flaws in their actual products, and half the engineering achievements in my list above were murdered by Sun's incompetent management.

Normally "private-key cryptography" is the antonym of "public-key cryptography", which is to say, conventional symmetric-key cryptography such as AES or Enigma. That's what "private-key cryptography" redirects to on Wikipedia. This article is about Astra breaking a message encrypted with a private-key cryptographic algorithm, but one that was already known to be weak. I'm guessing that if you had messages encrypted with weak public-key algorithms it could break those too.

You can just use 2-grams of Unicode code points.

I haven't used this radio, but I have definitely used a 2.4-kilobit-per-second internet connection productively. Raw TCP/IP with SLIP or PPP will work, and with VJ header compression it works reasonably well. What won't work well is loading a web page with a bunch of images and a megabyte of JavaScript.

If you wouldn't call them “absolutely critical” I wouldn't call you a typographer.

A lot of them are typographic in nature rather than manuscript.

ASCII is, as people have pointed out, a 7-bit code, so it can hold only 128 characters. When they added _ and ^ to it in 01967, they had to remove the ← and ↑ characters from ASCII-1963⁂. So there was no space for any of the characters —–“”×÷£°†‡¢§•€, which are absolutely critical even for English. "National variants" of ASCII might allocate space to some of them, or to other characters like ñ which are even more critical to the languages that use them.

If you're interested in how ASCII ended up that way, Tom Jennings wrote an excellent history: https://www.sensitiveresearch.com/Archive/CharCodeHist/index...

Of course, larger character sets that include ASCII as a subset do keep adding symbols: https://www.unicode.org/alloc/Pipeline.html and some programming languages do use non-ASCII symbols: https://docs.raku.org/language/operators

______

⁂ Smalltalk's continued use of ASCII-1963, among other things so that it could use ← as the assignment operator, is the reason that OO programmers got in the habit of using CamelCase, and are still doing so today, despite using a character set containing the underscore, and, typically, programming languages in which underscores are valid characters

It's a brilliant hack. It means that when you're dealing with valid UTF-8 strings, various kinds of string relationships enjoy a homomorphism between byte strings and Unicode strings. Specifically, where S and T are Unicode strings and E is the UTF-8 encoding operation:

• E(S concatenated with T) = E(S) concatenated with E(T)†

• S starts with T iff E(S) starts with E(T)

• S ends with T iff E(S) ends with E(T)

• S contains T iff E(T) contains E(T)

This means that, as long as you know your encoded strings don't contain invalid UTF-8, you can do a great deal of your string processing on the byte-encoded form, which is enormously faster than decoding the strings before doing the string processing, permits efficient radix-256 tries, and is much smaller in many common cases.

It also bounds the work you have to do if you're processing a string starting from the end, while certain other encodings require looking back in the string arbitrarily far to figure out how to interpret the bytes you're looking at. This is particularly important for Boyer–Moore string search, but in many cases it's also an express trip to getting your code featured on https://www.tumblr.com/accidentallyquadratic.

In short, yes.

______

†Surprisingly, even this most basic homomorphism is not true of many other character encodings, which may need extra bytes to be inserted in between.

I like being right so much that, when I'm wrong, I change my mind, despite how embarrassing that is.