And in Swift 5, `Error` conforms to itself so that you can have “untyped error”

In the beginning, Crusty In 2015, at WWDC, Dave Abrahams gave what I believe is still the greatest Swift talk ever given, and certainly the most …

I believe I can have the highest impact by providing the right education infrastructure to people who are a lot smarter than me and might already work in those fields.

Existentials and universals are [logical] “duals,” which means that one can be transformed into the other without losing its structure. So `AnySequence` is a universal type (generic) that’s equivalent to an explicit existential of `Sequence` (protocol). That’s why when you run into problems with protocols, your solution may be to convert it into generic structs (or vice versa). They solve the same problems in different ways with different trade-offs. And when you see “can only be used as a generic constraint,” what the compiler is really telling you is that protocols with associated types (PATs) don’t have an existential.

We could think of type-level-abstracted return types as doing the same thing but at the type level; you give a function generic arguments as inputs, and it gives a certain return type back. ​ This roughly follows the progression of `impl Trait` in Rust, where it was first introduced only for return types, then was generalized to be able to appear structurally in both argument and return types. We think this is a reasonable first step because it directly addresses the biggest functionality gap in the generics model. After that first step, there are a few fairly orthogonal language change discussions we can have, some of which are already underway

The company is growing fast, adding roughly a million users a month, and it has lofty goals to expand far beyond its old identity as a platform for logging rides and runs. Can it succeed?

Despite the easing of taboos and the rise of hookup apps, Americans are in the midst of a sex recession.

Personal site for John Feminella: software engineer · enthusiastic technologist · curiosity advocate

The women’s World Cup means all eyes are on the players right now, but their aesthetic has been enviable for a long time.

we may see more adults who know just the right emoji for a situation, but not the right facial expression. ​ You might expect that teens spend so much time in these new spaces because it makes them happy, but most data suggest that it does not.

Additionally, we want RC to be a place where everyone can focus their time and energy on becoming better programmers, not worrying that they don’t belong or feeling like they have to represent their entire race or gender because they’re in the extreme minority. We focus on diversity so Recursers can focus on programming.

...the evidence is that science has slowed enormously per dollar or hour spent. That evidence demands a large-scale institutional response. It should be a major subject in public policy, and at grant agencies and universities. Better understanding the cause of this phenomenon is important, and identifying ways to reverse it is one of the greatest opportunities to improve our future.

What would happen if I let myself take a break, let myself rest, gave myself some time off from the checklists and the to-do lists and the need to publicly appear productive? Maybe I’ll lose some followers, maybe I won’t be first in people’s minds when they’re thinking of someone to speak at their conference, maybe I’ll stop getting put into random lists of “Cool Thought Leaders To Follow On Twitter Dot Com.” But I’m not going to lose my job or my apartment or stop being able to pay my bills if I give myself a break from “trying to be productive literally every single day.” Realistically, I’m pretty sure I’ll still be able to find things like speaking opportunities if I want them. I’m not going to disappear if I put down my armor and let myself relax for a little while.

The message of Berlin is that not everything is set, that it has room for you.

The title was approved because at the time Cornell lacked any professional titles for people with academic appointments focused solely, or mostly, on teaching with little or no expectation of engagement in research.

@JadeMasterMath: There are lots of mathematical concepts which don’t have well written resources to learn about them. I think that explaining something in a clear way with a story arc can sometimes be enough. @jeremyjkun: Write about the topics that you learned, where there was a succinct phrase, picture, or idea that suddenly made it clear. Then arrange the whole blog post around getting the reader to that same understanding.

Both modes of definition need a way of insisting on a certain “minimality” for the structure of natural numbers that they are developing. The Peano axioms formulate this “minimality” by dependence upon the domino effect of truth in a mathematically inductive context. The Peano category approach formulates “minimality” by considering the position of the natural numbers as a discrete dynamical system, among all discrete dynamical systems.

Math is about more than just numbers. In this 'book' the language of math is visual, shown in shapes and patterns. This is a coloring book about group theory.

This has been so exciting for me because (reason). Thanks for letting me share. What’s important about that to you? Likes don’t count, you can’t respond to them. The triangle of friendship is consistency, vulnerability, and connection, with the latter being the base. I’m going to continue to mingle. It was lovely to meet you/y’all! “Hi, I’m [Jasdev]! Mind if I join you?” Suffixing clothing compliments by asking where they got it from. We all want to be both seen and supported—in love, friendships, and work.

flatMapLatest implementation via @SergDort pic.twitter.com/Upow6LRRDr— Rui Peres (@peres) June 5, 2019

There is an almost mystical element to this search for a quick fix; it is rooted in the same misguided beliefs that once led Ponce de Léon to search for a “fountain of youth” upon landing in the so-called New World, scouring the ponds, rivers, lagoons, and lakes of the Florida coastline for the mythic fountain. (There’s debate about whether this actually happened, or if the quest is itself a myth — but the myth’s endurance tells us about its staying power.) The fountain of youth would be the ultimate recharge — a reversal of time in a single instant. The contemporary recharge is about continuously undoing the day before, quickly erasing the wear and tear of living, creating a fresh start or a blank slate or a best self. But it’s aimed at a singular objective: productivity. At its heart, the myth of the recharge is about turning away from what might be broken about the structure of our society — the constancy of work, the absence of affordable healthcare, the expectation that we will be “plugged in” or “online” 24 hours a day — in search of short-term, generalizable solutions. We do not ask ourselves whether all this might be untenable, but instead what supplement we might take to make it a little more bearable. We rise and grind and rise and grind and sleep in between. We deplete, recharge, deplete, recharge.

The worst thing is how intellectually isolated we all are, how few people there are with whom we can share the insights that we find the most exciting, even among other mathematicians. For me personally I feel very frustrated that there is this huge part of my emotional life that most of the people whom I care about have no access to. ​ In a decade’s time, I hope I’m working on projects that I can’t even imagine now and have found a way to be a part of larger mathematical and public conversations.

If we want a name to fully describe the concept it points to, then it must be a very simple concept indeed. ​ But we still have to explain what a Mappable is. “What’s a Mappable? Well, it’s something you can map over!” is a terrible explanation! It’s literally just the grammatic expansion of the word. All it does is move the question one bit further ​ Functor is hard to learn. It is not hard to learn because it is named Functor. If you renamed it to anything else, you’d have just as hard of a time, and you’d be cutting off your student from all of the resources and information currently using the word “functor” to refer to that concept.

Keynote by Dr. Emily Riehl C◦mp◦se :: Conference http://www.composeconference.org/ May 18, 2017 Slides: http://www.math.jhu.edu/~eriehl/compose.pdf Monads have famously been used to model computational effects, although, curiously, the computer science literature presents them in a form that is scarcely recognizable to a category theorist — I’d say instead that a monad is just a monoid in the category of endofunctors, what’s the problem? ;) To a categorical eye, computational effects are modeled using the Kleisli category of a monad, a perspective which suggests another categorical tool that might be used to reason about computation. The Kleisli category is closely related to another device for categorical universal algebra called a Lawvere theory, which may be a more natural framework to model computation (an idea suggested by Gibbons, Hinze, Hyland, Plotkin, Power and certainly others). This talk will survey monads, Lawvere theories, and the relationships between them and illustrate the advantages and disadvantages of each framework through a variety of examples: lists, exceptions, side effects, input-output, probabilistic non-determinism, and continuations.

Facebook News Feed simultaneously increased the efficiency of distribution of new posts and pitted all such posts against each other in what was effectively a single giant attention arena, complete with live updating scoreboards on each post. It was as if the panopticon inverted itself overnight, as if a giant spotlight turned on and suddenly all of us performing on Facebook for approval realized we were all in the same auditorium, on one large, connected infinite stage, singing karaoke to the same audience at the same time. ​ As humans, we intuitively understand that some galling percentage of our happiness with our own status is relative. What matters is less our absolute status than how are we doing compared to those around us. By taking the scope of our status competitions virtual, we scaled them up in a way that we weren't entirely prepared for. Is it any surprise that seeing other people signaling so hard about how wonderful their lives are decreases our happiness? ​ Facebook, with its explicit attachment to the real world graph and its enforcement of a single public identity, is just a poor structural fit for the more complex social capital requirements of the young. ​ Every network has some ceiling on its ultimate number of contributors, and it is often a direct function of its proof of work. ​ This season, the color of the moment might be saffron. Why? Because someone cooler than me said so. Tech tends to prioritize growth at all costs given the non-rival, zero marginal cost qualities of digital information. In a world of abundance, that makes sense. However, technology still has much to learn from industries like fashion about how to proactively manage scarcity, which is important when goods are rivalrous. Since many types of status are relative, it is, by definition, rivalrous. There is some equivalent of crop rotation theory which applies to social networks, but it's not part of the standard tech playbook yet. ​ but if I have anything to offer on that front, it’s this: if you want control of your own happiness, don’t tie it to someone else’s scoreboard.

Selective Applicative Functors: Declare Your Effects Statically, Select Which to Execute Dynamically - GitHub - snowleopard/selective: Selective Applicative Functors: Declare Your Effects Staticall...