What does this output mean?

should this be inside the bracket??

hmm sure starting states can have an impact?

Special Track 3. (n.d.). Data for Policy CIC. Retrieved 8 March 2021, from https://dataforpolicy.org/data-fof-policy-2021/special-track-3/

Is this the first or second DSI? Did one happen in 2020?

QUESTION: What exactly does nix-shell execute from the Nix expression (i.e., shell.nix, default.nix, etc.)?

ANSWER: Based on my current understanding, the answer is everything. It calls $stdenv/setup (see annotation below) to set up the most basic environment variables (TODO: expand on this), and "injects" the most common tools (e.g., gcc, sed) into it.

It also defines the phases (TODO: verify this) and builder functions, such as genericBuilder. For example, the default builder is just two lines:

source $stdenv/setup
genericBuild

TODO: pkgs/stdenv/generic/builder.sh is a mystery though.

QUESTION: Once dropping into nix-shell, how do I know what phases to execute by looking at a default.nix? (E.g., [..]freeswitch/default.nix)

ANSWER: As far as I can tell, one can override the phases in their Nix build expression (to build the derivation, see at the bottom), but they won't get executed as only the $stdenv/setup (see above) will get sourced, and no builders are called that, in return, invoke the phases (again, see above).

So if one is using nix-shell

• to create/hack on a package, the person has to manually invoke the builder or phases (TODO: still fuzzy on this subject)

• to set up an environment, then one doesn't even have to worry about builders/phases because we just use nix-shell to clear the environment and to inject tools that we need for a given task

QUESTION: When dropping into nix-shell, is this Nix expression (i.e., freeswitch/default.nix) executed? Or just parts of it?

ANSWER: As stated above, all of the input Nix expression is evaluated, but no builders and build phases are called; although, nothing prevents one to override the phases, in case they are creating/hacking on a package.

QUESTION:

The command nix-shell will build the dependencies of the specified derivation, but not the derivation itself.

What is the "derivation" here exactly? I know that it is a build expression, but does that mean the default.nix (or other Nix expression) nix-shell is invoked with?

^{This statement also seems like a contradiction with how `nix-shell` works (i.e., if one issues `nix-shell -p curl`, then `curl` will be available in that sub-shell), but `-p` acts like a shortcut to as if `curl` had been listed in `buildInputs` so this is not the case.}

ANSWER: I have the feeling my confusion comes from the fact that the term "derivation" is used ambiguously in the manuals, sometimes to mean multiple things (see list below).

TODO: Substantiate this claim, and make sure that it not coming from my misunderstanding certain topics.

• Nix build expression (such as default.nix) whose output is going to become the store derivation itself (see last item at the bottom about the Nix manual's glossary definition)

• store derivation.

Had multiple cracks at unambiguously define what a derivation is, and here's a list of these:

• What is the purpose of nix-instantiate? What is a store-derivation? (probably the best try yet)

• What is a Nix expression in regard to Nix package management? (feels sloppier, but commenter mentions ATerm, adding the possibility of making it very specific)

• Closure vs derivation in the Nix package manager (very short, and will have to be re-written, but adds closures to the mix)

• There is now a glossary definition of a derivation in the Nix manual; see this annotation why I find it problematic

QUESTION: What is the difference between nix-shell -p and nix-shell invoked with a Nix expression of mkShell (or other that achieves the similar effect)?

QUESTION: nix-shell does not create a sub-shell, so what does it do? (clarification: so nix-shell indeed does it; I confused it with nix shell)

Now define this? Does elearning mean strictly online? Does it mean with technology (like apps)?

Is this notion -- that "reading is also a discourse act" -- new or novel to you?

[[discrete probability distribution]] in contrast to [[continuous distribution]] by the number of outcomes : [[discrete probability distribution]] only have finite number of possible outcomes??????

If this was a sign of luxury and power, eating lying down is very uncomfortable, so if it was uncomfortable, why would it still be a luxury?

How does it detect that it's being run non-interactively as part of a script?

Is that distinct/different from detecting whether the command is being piped?

Can't expect / unbuffer / etc. (whatever this is attempting to contrast itself with) be easily invoked directly from shell prompt or script too??

Okay, I guess you have to know more about how expect is invoked to understand what they mean. One glance at the examples, comparing them, and all becomes clear:

#!/bin/sh
empty -f -i in -o out telnet foo.bar.com
empty -w -i out -o in "ogin:" "luser\n"

I didn't realize that expect required/expected (no pun intended) to be used in scripts with its own shebang line:

#!/usr/bin/expect

spawn telnet foo.bar.com 
expect ogin {send luser\r}

That does make it less easy/normal to use expect within a shell script.

I was coming to the expect project from/for the unbuffer command, which by contrast, is quite easy to include/use in a shell script -- almost the same as empty, in fact. (Seems like almost a mismatch to have unbuffer command in expect toolkit then. Or is expect command the only odd one out in that toolkit?)

https://boardgamegeek.com/boardgame/183284/factory-funner/versions

And now there are two versions with the nickname "Second edition": 2018 https://boardgamegeek.com/boardgameversion/404596/second-edition 2021 https://boardgamegeek.com/boardgameversion/556765/second-edition

and a 3rd edition published prior to the current/new 2nd edition: 2019 https://boardgamegeek.com/boardgameversion/486693/third-edition

Confusing all around.

But I think the bottom line is that the 2021 version is in fact the same game and the newest rules tweaks:

1. Added a sixth player
2. Official variant to play without the quick grab element.

What does the (dashed) arrow for fork() mean? Why does it point that way? Which one is a fork of / has forked which one?

Only answered:

• who maintains
• what the license is

Berman is using the specialized theories of linguistic anthropology to analyze life in Jajikon. How do these theories take us deeper into the worldview of her hosts? Or perhaps do we not need all this scientific mumbojumbo to understand how people avoid giving?

Are there other Pacific peoples who use indirect speaking because they believe direct speech is dangerous? Can you think of examples of indirect speech here in Hawai‘i or other Pacific places which connect them with Micronesia?

These two sentences begin a story that will span the entire chapter. Using what you know about the rhetoric of ethnography, please tell me how Berman uses immediate and distanced narratives, as well as confessional and realistic styles, in order to tell her story across this whole chapter?

Goodness. Can someone explain what this passage means to me? It seems to be central to her argument in this book, but lines like "If actions lead to power as opposed to the other way around" seem very difficult to understand. What does this sentence means? Can you explain it, or do you need help understanding it? I guess this is a request for a comprehension check.

Dvorak taught us to think carefully about images. What is up with Berman's decision to pixelate out people's faces? What did you think of that?

I am curious to know what people think about this case of adoption. Berman seems to show a situation. We tend to be pro-Pacific Island culture and pro-human rights, but in this case, it seems a woman's right to raise her child is in tension with a cultural system where the elderly have power and the young must submit. What were your reactions to this passage? Am I mischaracterizing it?

That's a tough one. I can see it both ways.

in the case of

briefly mentioning a subject but not going into it in detail the topic/subject need not be related at all (it sounds like).

What about in the case fo:

is defined as going off in a different direction. Does the fact that it's going off in a different direction imply that it at least starts out connected/related to the original (starting point) subject (as it does in the geometry sense of tangential)? Or does it permit "jumping" to another topic (in another direction) without being related/connected at all??

I don't think I like this definition very much. It doesn't quite fit the sense I'm trying to use it for in my tag:

tangentially related content (aside)

Ah, here's a definition that matches what I thought it meant (one of the senses anyway): https://hyp.is/3Bn2bpZ7Eeu3Ok8vg03AVA/www.merriam-webster.com/dictionary/tangential

We know from Hau‘ofa that islanders are mobile. But given the fact that Monty includes Maui and a Scottish missionary are feature characters in the book, and also given the fact that he now includes in his ethnography the Tannaese diaspore in Port Vila, what is the topic of Monty's book? Tanna? Samaria? Islanders? Something else?

Monty seems to believe that tourism is a pretty good deal for Tanna. Given what we know about tourism in Hawai‘i (and perhaps other places you'd like to share about), do you agree or disagree with him? And why?

Monty seems to be making an argument here that anthropologists and islanders are very similar. What is his argument here and do you agree with it?

not necessarily incompatible in all senses.

so is this only a concern/possibility when the word in question is a polyseme?

but there is nothing preventing the queen from being a mother

The meaning of the "incompatibility" relation seems really ambiguous. What does that mean precisely?

And how would we know for sure if an incompatibility (such as a peach is not a plum) or lack of incompatibility (a queen can be a mother and a mother can be a queen) is a sufficient condition to cause it to be or not be a co-hyponym?

Oh. I guess it says

Co-hyponyms are often but not always related to one another by the relation of incompatibility.

so it actually can't ever be used to prove or disprove (sufficient/necessary condition) that something is a co-hyponym. So that observation, while interesting, is not helpful in a practical / deterministic way...

So I think what this saying, rather indirectly (from the other direction), if I'm understanding correctly, is that the relationships that can be inferred from looking at a taxonomy are ambiguous, because a taxonomy includes 2 kinds of relationships, but encodes them in the same way (conflates them together as if they were both hyponyms--er, well, this is saying that the are both kinds of hyponyms):

• "An X is a Y" (simple hyponymy)
• "An X is a kind/type of Y".

Actually, I may have read it wrong / misunderstood it... While it's not ruling out that simple hyponymy may sometimes be used in a taxonomy, it is be saying that the "second relation" is "more specifically under the concept of taxonomy" ... which is not really clear, but seems to mean that it is more appropriate / better for use as a criterion in a taxonomy.

Okay, so define "simple hyponymy" and name the other kind of hyponymy that is referenced here.

What's the connection between a series and the function?

-- because of the phrase: "the Taylor series of a ... function "

What, then, is the difference between a semantic domain and a semantic field? The way they are used here, it's almost as if they are listing them in order to emphasis that they are synonyms ... but I'm not sure.

From the later examples of basketball (https://hyp.is/ynKbXI1BEeuEheME3sLYrQ/en.wikipedia.org/wiki/Semantic_domain) and coffee shop, however, I am pretty certain that semantic domain is quite different from (broader than) semantic field.

(Not answered on this stub article)

What, precisely, is the distinction/difference between a semantic class and a semantic field? At the very least, you would say that they are themselves both very much within the same semantic field.

So, is a semantic class distinct from a semantic field in that semantic class is a more well-defined/clear-cut semantic field? And a semantic field is a more fluid, nebulous, not well-defined field (in the same sense as a magnetic field, which has no distinct boundary whatsoever, only a decay as you move further away from its source) ("semantic fields are constantly flowing into each other")?

If so, could you even say that a semantic class is a kind of (hyponym) of semantic field?

Maybe I should pose this question on a semantics forum.

Would this be referring, then, to explicit meaning or implicit meaning -- or neither?

Speaking of ambiguity...

Are the examples in the list "such as a morpheme, word, or sentence" examples of

• aspects of a linguistic unit or of:
• linguistic units themselves ?

Unless you are already fairly familiar with those terms -- in particular, linguistic unit -- it may not be clear.

I believe these are given as examples of "linguistic unit", in order to clarify what we mean by "linguistic unit" — perhaps (ironically) precisely because many people would be unfamiliar with that expression/term.

Is this a polyseme?

Or is that only the case if the different distinct senses are all within the same "field"?

Here is the place for awe-inspiring numbers.

Does UMaine hire its own graduates? Or do they consider this inbreeding?

BU Epi COVID Response Corps on Twitter. (2021). Twitter. Retrieved 13 February 2021, from https://twitter.com/EpiCOVIDCorps/status/1359700470302990348

BU Epi COVID Response Corps on Twitter. (2021). Twitter. Retrieved 13 February 2021, from https://twitter.com/EpiCOVIDCorps/status/1359700470302990348

I had similar question... how to get --servername support.

I had this question too, but didn't know that was the question I had... :)

More generally, my question is: How can I programmatically / from command line, launch a .desktop file?

answer to: https://hyp.is/wjrI5ogQEeuJKP-UNuyw-A/askubuntu.com/questions/8252/how-to-launch-default-web-browser-from-the-terminal

Q: 那岂不是会出问题? 有什么事件会被触发吗?

Q: 标记node为不可调度本来就不会驱逐正在运行的node吧 A: daemonset中的pod是可以在后面动态添加的

那为为什么叫 kubeconfig?而不是kube-credentials-path? 参见 https://github.com/zecke/Kubernetes/blob/master/docs/user-guide/kubeconfig-file.md kubeconfig 就是存鉴权信息地方

有没有某种机制是用来检查这个异常状态的?

does this trajectory say something: Winston-Salem-Durham-hill above Harlem.... is this person a long way from home?

Am I missing the link somewhere in plain sight?

I think it is, yes.

Wine was given as an example of a process VM above.

Why not just make this document empty (besides a link) and link/redirect to the canonical version?

That way it is impossible for them to disagree.

For how detailed and insightful his analysis was -- which didn't elaborate or even touch on his not understanding the reason for adding the semicolon -- it sure appeared like he knew what it was for. Otherwise, the whole issue would/should have been about how he didn't understand that, not on how to keep adding the semicolon but do so in a faster way!

Then again, this comment from 3 months afterwards, indicates he may not think they are even necessary: https://github.com/rails/sprockets/issues/388#issuecomment-252417741

Anyway, just in case he really didn't know, the comment shortly below partly answers the question:

Since the common problem with concatenating JavaScript files is the lack of semicolons, automatically adding one (that, like Sam said, will then be removed by the minifier if it's unnecessary) seems on the surface to be a perfectly fine speed optimization.

This also alludes to the problem: https://github.com/rails/sprockets/issues/388#issuecomment-257312994

But the explicit answer/explanation to this question still remains unspoken: because if you don't add them between concatenated files -- as I discovered just to day -- you will run into this error:

   (intermediate value)(...) is not a function
       at something.source.js:1

, apparently because when it concatenated those 2 files together, it tried to evaluate it as:

   ({
     // other.js
   })()
   (function() {
     // something.js
   })();

It makes sense that a ; is needed.

https://github.com/rails/sprockets/issues/162 was already closed as duplicated (so this just creates another duplicate).

Technically this could be added there.

Oh, I see, it was from so long ago (2015), that it would probably be frowned upon to reopen such an old issue.

La pensée n'est donc que traces. Dirais-tu que la voix, sans technologie d'enregistrement, n'est que pensée dans la mesure où elle a une « conscience » pour la recevoir, c'est-à-dire une surface sur laquelle s'inscrire?

On pourrait même stipuler que la pensée n'est autre qu'énergie transformée et emmagasinée. Mes cordes vocales produisent des ondes sonores (une forme d'énergie) qui sont ensuite reçues par un système auditif qui l'interprète et envoie des signaux électromagnétique (toujours de l'énergie) au cerveau.

matérialisme dialectique?

Serait-il plus clair de parler de réalisme direct, « naïf »?

Il faudrait définir précisément ce que "technological environment" signifie, et pourquoi pas plutôt "technical environment" par exemple (sans vouloir couper les cheveux en 4) ?

Ce "paradoxe de l'accès" pourrait aussi être comparé avec la question de l'accès aux données numériques ? Les données sont produites, stockées, mais sont-elles encore accessibles, compréhensibles (par des machines ou des humains) ou exploitables ?

Comment cette définition minimale interagit-elle avec la définition de monde en logique modale comme ensemble logique (non-contradictoire) de propositions nécessaires et contingentes (Leibniz)? Pour ses fins méthodologiques, les logiciens contemporains (XXe) semblent fonder une ontologie non sur les objets, mais des propositions appréhendables par le langage. Il semble, aux premiers abords, que la logique modale reformule un certain idéalisme. Mais la position des logiciens est-elle réellement irréconciliable avec celle du new materialism?

https://www.reddit.com/r/BehSciAsk/comments/jkzuig/ideas_for_discussion_how_can_research_interface/?utm_source=share&utm_medium=web2x&context=3

jazz and 'city vs rustic' as hot and cold? don't follow rly

they can no longer be CONTAINED? is he saying they can no longer be blissfully ignored like above?

what are these theaters he's talking about??

ReconfigBehSci. (2020, November 21). RT @DrEricDing: Good question for immunologists like @michaelmina_lab @VirusesImmunity and @PeterHotez. Https://t.co/Rs1zaUPznm [Tweet]. @SciBeh. https://twitter.com/SciBeh/status/1334804615842439170

Imagining the Next Decade of Behavioral Science. (2020, January 20). Behavioral Scientist. https://behavioralscientist.org/imagining-the-next-decade-future-of-behavioral-science/

So what happens if a task returns a Left signal?? Will it still go Right? Will it error?

I don't think we would/should really want to make this the "success" (Right) path and :credit_card be the "failure" (Left) track.

Maybe it's okay to repurpose Left and Right for something other than failure/success ... but only if we can actually change the default semantic of those signals/outputs. Is that possible? Maybe there's a way to override or delete the default outputs?

QUESTION: So when I see $out in a builder script, it refers to the default output path because the output attribute in the Nix expression has never been explicitly set, right?

Organically related to the annotation regarding my nix-shell confusion.

The dissection of this definition to show why I find it lacking:

A description of a build action.

The first (couple) time(s) I read the manuals, this description popped up in many places, and I identified it with Nix expression every time, thinking that a derivation is a synonym for Nix expression.

Maybe it is, because it clearly tries to disambiguate between store derivations and derivation in the last sentence.

The result of a derivation is a store object.

Is this store object the same as a store derivation?

Derivations are typically specified in Nix expressions using the `derivation primitive. These are translated into low-level store derivations (implicitly by nix-env and nix-build, or explicitly by nix-instantiate).

QUESTION: So, the part of the Nix build expression (such as default.nix) where the derivation primitive is called (explicitly or implicitly, as in mkDerivation) is the derivation, that will be ultimately be translated into store derivations?

ANSWER: Start at section 15.4 Derivation.

QUESTION: Also, why is typically used here? Can one define derivations outside of Nix expressions?

ANSWER(?): One could I guess, because store derivations are ATerms (see annotation at the top), and the Nix expression language is just a tool to translate parameterized build actions into concrete terms to build a software package. The store derivations could be achieved using different means; e.g., the way Guix uses Guile scheme to get the same result))

I believe, that originally, derivation was simply a synonym to store derivation. Maybe it still is, and I'm just having difficulties with reading comprehension but I think the following would be less misleading (to me and apart from re-writing the very first sentence):

Derivations are typically the result of Nix expressions calling the derivation primitive explicitly, or implicitly usingmkDerivation`. These are translated into low-level store derivations (implicitly by nix-env and nix-build, or explicitly by nix-instantiate).

QUESTION: Does this refer to pkgs/stdenv/generic/setup.sh? According to 6.5 Phases in the Nixpkgs manual?

ANSWER: I'm pretty sure it does. It sets up the environment (not sure how yet; I see the env vars, but not the basic commands - sed, awk, etc. - that are listed below) and defines a bunch of functions (such as genericBuilder) but it doesn't call these functions!

this is another key topic. Also:

• substitute vs. substituter => this (I think)

See annotations with the substitute tag

binary caches tie in with substitutes somehow; get to the bottom of it. See annotations with the substitute tag.

Maybe this?

Why?

Answer is below in the manual: https://hyp.is/qRSFdnCJEeueY8NWtMIeHw/toraritte.github.io/saves/Nix-Package-Manager-Guide-Version-2.3.10.html

Would have been nice to link these to the install chapter where single- and multi-user modes were mentioned.

How would this look in a topic-based documentation? I would think that his chapter would be listed in the pre-requisites, and it could be used to buld different reading paths (or assemblies in DocBook, I believe) such as practical, depth-first (if there are people like me who want to understand everything first), etc.

https://en.wikipedia.org/wiki/Reentrancy_(computing)

What is happening here exactly?

nix-shell's syntax synopsis always bugged because it looks like this

SYNOPSIS
nix-shell [--arg name value] [--argstr name value] [{--attr | -A} attrPath] [--command cmd] [--run cmd] [--exclude regexp] [--pure] [--keep name] {{--packages | -p} packages...  | [path]}

and the canonical example is nix-shell '<nixpkgs>' -A pan; what tripped me up is that path is usually the first in examples, and I thought that the position of arguments are strict. As it turns out, nix-shell -A pan '<nixpkgs> is just as valid.

Side note<br> Apparently there is no standard for man pages. See 1, 2.

'<nixpkgs>' path is the one specified in the NIX_PATH environment variable, and -A pan looks up the pan attribute in pkgs/top-level/all-packages.nix in the Nixpkgs repo.

QUESTION: What is a fixed-point of a function?

ANSWER: See this video) at least, and the Fixed-point (mathematics)) wikipedia article:

In mathematics, a fixed point (sometimes shortened to fixpoint, also known as an invariant point) of a function is an element of the function's domain that is mapped to itself by the function. That is to say, c is a fixed point of the function f if f(c) = c. This means

f(f(...f(c)...)) = f n(c) = c

an important terminating consideration when recursively computing f. A set of fixed points is sometimes called a fixed set.

For example, if f is defined on the real numbers by f(x)=x^{2}-3x+4,}, then 2 is a fixed point of f, because f(2) = 2.

There is also the wiki article fixed-point combinator that actually plays a role here, but read through the articles in this order.

Then dissect the Stackoverflow thread What is a Y combinator?, and pay attention to the comments! For example:

According to Mike Vanier's description, your definition for Y is actually not a combinator because it's recursive. Under "Eliminating (most) explicit recursion (lazy version)" he has the lazy scheme equivalent of your C# code but explains in point 2: "It is not a combinator, because the Y in the body of the definition is a free variable which is only bound once the definition is complete..." I think the cool thing about Y-combinators is that they produce recursion by evaluating the fixed-point of a function. In this way, they don't need explicit recursion. – GrantJ Jul 18 '11 at 0:02

(wut?)

Other resources in no particular order:

• google search for "fixpoint evaluation fixed point combinator explained"
• Cornell's CS 6110 S17 Lecture 5
• google search for "fixed-point of a function"
• Fixed-point theorem (wikipedia)
• How can I find the fixed points of a function? (math stackexchange)
• The Y Combinator (Slight Return) (see the "Fixpoint of functions" section)
• Clear, intuitive derivation of the fixed-point combinator (Y combinator)? (computer science stackexchange)
• Fixed-Point Combinators (stackoverflow)
• Fixed-point combinator (HandWiki)

QUESTION: How the hell did they come up with the idea of using this with Nix and package management? (..and who? I remember a video saved somewhere, but maybe that was about overlays)

QUESTION: ... and how does it work in this context?

ANSWER: Well, not an answer yet, but this may be something in the right direction:

http://blog.tpleyer.de/posts/2020-01-29-Nix-overlay-evaluation-example.html

QUESTION: What is ldconfig cache?

QUESTION: What is libc and why does Bash need it?

QUESTION: So the Nix store houses derivations and not the built packages?

QUESTION: Are the hashes in the Nix store not unique?

How can they exist and it still be considered pure??

I guess that's not quite the same / as bad as saying something had side effects in a purely functional programming context, right?

Question to myself: Is not having to think about it actually a good goal to have? Is it at odds with making intentional/well-considered decisions?  Obviously there are still many of interesting decisions to make even when using a framework that provides conventions and standardization and makes some decisions for you...

What is the opposite of free content?

The opposite of free/open-source software is proprietary software or non-free software (https://en.wikipedia.org/wiki/Proprietary_software).

So should we call the opposite of free content "non-free content"? Or "proprietary content"?

Seems likes either would be fine.

Looks like https://en.wikipedia.org/wiki/Wikipedia:Non-free_content prefers the term "non-free content".

Couldn't find anyone contrasting these 2 terms (like I could no doubt find for software):

• https://duckduckgo.com/?q=+%22non-free+content%22+%22free+content%22
• https://duckduckgo.com/?q=%22proprietary+content%22+%22free+content%22&ia=web

Not to be confused with:

• paid content ... just like:
• free content should not be confused with gratis content (?)
• free software should not be confused with freeware

Vries, L. de, Weijer, M. van de, Pelt, D., Ligthart, L., Willemsen, G., Boomsma, D., Geus, E. de, & Bartels, M. (2021). Individual differences in the effect of the COVID-19 pandemic on optimism and meaning in life. PsyArXiv. https://doi.org/10.31234/osf.io/b2ge6

Didn't they mean what mkDerivation requires?

I have been jumping around in this manual, so not sure about what arguments does derivation require.

The author is asking a rhetorical question and answering it immediately. He is doing this not only to clear one of the audience's questions regarding the consequences of Texas situations, but also to make the government officials more guilty for leaving Texas in this situation.

How is this better than simply:

Add.run(x: x, y: 3)

?

I guess if we did that we would also have to remember to handle merging errors from that outcome into self...

TODO: Find other sources about this topic. I remember this mentioned already (and it makes) sense, but need to learn more.

TODO: What is a better alternative? An own repo? Flakes? Can cachix help?

It says right below that pinning can help but keep looking.

When package reproducibility become a major concern, as it is the case in this tutorial, it is preferable to refer to a pinned version of the nixpkgs repository instead — i.e, a specific commit of the repository or an immutable archived tarball. The ability to pin the version of nixpkgs is powerful, it will ensure that a package is always constructed from the same Nix source. As we go deeper in the tutorial we avoid using channels in favor of pinned environments.

what is the meaning of this???

Question: How do they measure the value of import services?

最大的sigma代数是\(\mathcal{F}\)?

• sigma代数的大小如何理解？
• 信息的定义？

Dyer, C. (2021). Covid 19: How to feel safe working on the front line—your legal and ethical questions answered. BMJ, 372, n179. https://doi.org/10.1136/bmj.n179

Does this relate and increase how it impacts the pollution aspect compared to if it had been someone without asthma?

How would this relate and compare to other countries in general? Or in more specific areas in places that have higher amounts of people dying from pollution?