I can second this, after finishing my intro Japanese classes I was able to parse the grammar of most sentences. Memorizing vocab was the hard part, so I used OCR on manga pages and then Yomitan to hover over and see word definitions (in English).
Most existing mainstream languages aren’t expressive enough to encode these invariants. For languages outside of the mainstream, Lean 4 is a language supporting verification, and it’s also a full programming language, so you can write your proofs/theorems in the same language that you program in.
In most languages you can express any invariant, sure, but you can't prove that the invariant is upheld unless you run the program.
For example a NonNegativeInteger type in most languages would just have a constructor that raises an exception if provided with a negative number. But in languages with proofs, the compiler can prevent you from constructing values of this type at all unless you have a corresponding proof that the value can't be negative (for example, the value is a result of squaring a real number).
Most roll their own for three reasons: performance, context, and error handling. Bison/Menhir et al. are easy to write a grammar and get started with, but in exchange you get less flexibility overall. It becomes difficult to handle context-sensitive parts, do error recovery, and give the user meaningful errors that describe exactly what’s wrong. Usually if there’s a small syntax error we want to try to tell the user how to fix it instead of just producing “Syntax error”, and that requires being able to fix the input and keep parsing.
Menhir has a new mode where the parser is driven externally; this allows your code to drive the entire thing, which requires a lot more machinery than fire-and-forget but also affords you more flexibility.
If you're parsing a new language that you're trying to define, I do recommend using a parser generator to check your grammar, even if your "real" parser is handwritten for good reasons. A parser generator will insist on your grammar being unambiguous, or at least tell you where it is ambiguous. Without this sanity check, your unconstrained handwritten parser is almost guaranteed to not actually parse the language you think it parses.
This explains why i have been finding his recent videos somewhat disjointed/disorganized and titles click-baity. The quality of the content has most certainly gone down.
3blue1brown has great math visualizations. I find the top 10% of YouTube videos are worth the time over reading, and the bottom 90% are comparable or slower. Those are also nice though because you can put them on while doing other stuff, like eating or doing the laundry.
Part of the public pushback is that people almost always drive the “feels like” speed and not the posted speedlimit. We build 6 lane roads and then wonder why people go 50mph when it’s 35 posted, it’s because it’s 6 lanes and 35 feels slow. Cities profit from this in the form of speed cameras, which is why they’ve been outlawed in a lot of places.
The driver blithely keeping with the flow of traffic is not the one I am worried about. It is the one who is aggressively trying to cut through the flow of traffic while putting everyone and themselves in danger that I worry about.
I love when cities time their lights so that aggressive drivers just get hit with waiting at a red light while driving the speed limit means hitting greens for long stretches.
Yes, and about twice I've seen this done really right, wherein they post signs of the synchronization speed (e.g., "Lights Timed for 35mph"). I just get in sync with one light and adjust speed and it feels almost magic to go a few miles hitting every green light (it kind of is the macic of math).
It'd be cool if more roads were implemented that way.
I have the same in my area, but instead the lights are synchronized to slow traffic as much as possible. They literally coordinate to make you stop at as many lights as possible and grid lock at rush hour so the highway doesn't get flooded.
I walk my kids to school, but when I do drive the 1.1 miles there are no less than 12 stoplights/stop signs.
There's a part of downtown here that is known for being set up like this. However, it's been a bust while there's been a lot of construction blocking lanes so nothing moves at speed.
Sure, some people will get hit with the reds. Some people will learn the timing and learn that you can run just one red and then hit all greens, or that it will save you 5+min if you hammer down and pull a "clearly not ok" pass to get around some idiot who's going too slow to make the green timing.
So yeah, you're reducing speeding, number go up, pat yourself on the back. But you're also increasing the incidence of something rarer than speeding, but way worse.
This is the same problem that 4-way stops at roads that don't deserve them create, you're basically teaching people that the signage is bullshit.
Upping the speed limit reduces the incidence of the latter because just about everyone has a "fuck this I'm weaving" threshold and the number of people who hit it goes down when you reduce the incidence of rolling clusters of traffic caused by the handful of people who religiously follow the speed limit even when not appropriate.
If the speeds aren’t appropriate for the built environment, then the limits should be changed or the environment should be changed. Enforcement of the law should be consistent regardless of the quality of the law.
The speeds are appropriate for the roads generally. I mean, at the lowest level speed limits are a matter of social consensus so the broad public is tautologically correct.
The problem is that knocking the magic number on the sign down by 5-15 and then simply not enforcing it too seriously results in less screeching Karens harassing the politicians who then harass the bureaucracy than taking a hard line about "well akshually this is the engineered speed for the road".
The speed cameras in San Francisco have to result in lowered speeding over the 18 month period they're active. If they don't, they will be pulled. Seems pretty well-designed. Perhaps the fines are weak but it's good that they're there.
Just because a road "feels" like it can handle more speed does not mean that it is. The wider streets are built to handle the volume of cars, not necessarily meant to become a speed way. There are several 6 lane roads in my area while being wide and well built still have many intersections only controlled by stop signs for the smaller streets with multiple intersections controlled by stop lights at the larger cross streets.
People unable to recognize this and only driving by the feels are the problem. Hand wavy comments like yours suggesting using the feels as being okay do not help the situation
Basing your speed on what the road looks like may not be “okay” or “legal”, but it’s what people do. It’s just not useful to claim that individual people are the problem when this is something that is overwhelmingly true across the entire population—-a broader solution than individual responsibility is the only thing that will actually work.
Speeds are fundamentally a tradeoff between risk and reward. In nominally democratic societies we place these thresholds based on some approximation of social consensus. The general public literally cannot be wrong because their rough consensus, the fat part of the bell curve if you will, is what determines what the right speed is.
Your comment is literally the principal Skinner "no it's everyone else who's wrong" meme.
Um, no it’s not. If you think that roads are built with no consideration for anything other than if the infrastructure will support traffic at a certain speed then you’re just not thinking about things. Speed limits are set with many factors in that decision. Things like noise and safety are major parts of that. Someone else has already suggested a lame reason as a noise complaint made by a single person, but cars moving faster make more noise. Cars moving faster limits the time a car at a stop sign can safely navigate causing traffic at cross streets.
Regardless of what you think, speed limits are not set in place just to ruin your day because you can’t leave on time and constantly need to “make up time”. They are not arbitrary decisions just because you haven’t considered all of the factors involved.
Now you're relying on Jimmy "Buck" Rawgers born and raised in Billton county working at the DOT setting the speed limits and the traffic light cadence.
How many roads are 35 when they should be 50 simply because some local yokel asshole made a stink at city counsel 10 years ago and now it's impossible to change?
There is no builtin setting in iOS to disable it. However most 3rd party keyboards don't have it, as implementing it without OS support is a huge pain.
Why is it hard? In principle you render an image instead of discrete buttons, and do your hit testing manually. Sure, it’s more annoying than just having your OS tell you what key got hit, but keyboard makers are doing way fancier stuff just fine (e.g. Swype).
Apple's keyboard receives more information, to put it simply. It doesn't get told that a touch was at a particular point, but the entire fuzzy area. Allowing you to use circular occlusion and other things to choose between side-by-side buttons and override the predictive behaviour when it is the wrong choice.
A third-party maker gets a single point - usually several in short succession, but still it requires more math to work out where the edges of the finger are pressing, to help determine which direction you're moving. So most just... Don't.
this sounds nice, but neglects the fact that (1) materials cost has gone up and (2) zoning requirements exist. (1) means its just more expensive to build overall, and (2) means that a lot of proposals for apartment complexes get voted down.
I'm not neglecting those facts. 2) is almost the entirety of the problem. the call to action of "build more" is not wishful thinking that someone will donate free houses to the public. the call to action is to vote for politicians who will remove the near-universal smothering red tape that prevents any kind of meaningful new housing construction
Part of building more is getting government (mostly) out of it so that things like zoning laws don't hamper new development. Obviously that is very hard to do at a local level when incumbent homeowners' housing values would be cut in half overnight.
Actual NIMBY/YIMBY fights look like one level of government representing a lot of people who can't afford a primary residence fighting against a different level of government representing a lot of incumbent primary residence owners who are concerned on a personal level about the negative externalities of more people being able to live in their neighborhood. Government is happening no matter what.
This is happening in california. In fact there are three current situations:
1/SB9 cutting R1 lots in half
2/ ADU laws, which let you build up to 3 homes/units where there was one and further, can be combined with SB 9
3/ AB2011 which lets you turn defunct strip malls into housing
Honestly, this plus things like PermitFlow make me feel like we will be able to build enough. The issue will be making sure the housing is affordable rather than expensive and empty.
You're not wrong. There are multiple aspects of government involvement that require untangling which includes federally backed mortgages that allow banks to be more lax on loan terms (which is how we got 30 year loans and Trump proposing a 50 year)
can you please explain how these graphics are supposed to support your argument? it's not clear to me and i'm trying to understand the georgist POV.
nonetheless, materials and the cost of labor are the most significant costs for new buildings. not land, taxes, or zoning regulations. here is one example where this is a fact: www.vermontpublic.org/local-news/2024-05-23/uvm-halts-student-housing-project-construction-costs-workforce-shortage
Switch from "national level" tab to "metro level", and select los angeles for an extreme example. Look at the the figures right of the map, that says "share of SFD units build before 1980 with a land share of" and compare the figures between 2012 and 2024. Just by eyeballing the percentages, it looks like the land share went from 50-60% to 70-80%. This is confirmed if you sum up the figures in a spreadsheet, you go from an average share of 51% to 72%.
You can compare this to overall housing prices in the LA area[1], prices in 2024 is 262.7% of 2012 prices. Suppose you have a $100k house in 2012, that will worth $262k in 2024, an appreciation of $162k. Using the land value percentages above, the land value of the houses are $51k and $188k respectively, an appreciation of $137k. That means 85% of the appreciation was in land, not because building materials got more expensive or whatever.
Yes, I agree. Maybe if you’re a fast reader icons don’t do much, but for people who are illiterate (20% of America) they figure out how to use tech by memorizing the icons and locations of buttons.
There's illiteracy, and there's functional illiteracy. They're not the same, and people often confuse the two. A literally illiterate person (ha!) wouldn't make headway with almost any realistic computer interface, icons or not.
The 20% statistic is about people who have great trouble reading and comprehending simple sentences, not discerning individual words. It's tragic and debilitating, but such people could muddle through a simple interface with textual labels. A truly illiterate person couldn't.
Well, if you're unable to read, you're not going to figure out what the buttons do by reading the textual labels :p
Further, if you have difficulty reading, it's easier to parse the meaning of an abstract symbol, so you'd use that instead of a textual label when available. (I say this as someone who is a really slow reader. I use icons when I can)
[0] https://old.reddit.com/r/CryptoCurrency/comments/1jki1lj/pol...
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