I const a variable in an if statement but I can't use the variable out of the statement    const a = 1  const b = 1  if (a == b) {   const c = 1   console.log(c) } console.log(c)     fist it gives me c ( in the if statement) then it gives me an error(out of the if statement)
What is the scope of variables in javascript? Do they have the same scope inside as opposed to outside a function? Or does it even matter? Also, where are the variables stored if they are defined globally?
Protect email addresses in the user description from bots I've noticed that emails are not protected in the user description. For example  entered his email and when viewing the source code of the page it is plain text that malicious bots could harvest and exploit to spam. It would be nice if email addresses were automatically encoded to prevent this. I was doing graph theory homework. I was counting the spaning trees of graph G. Such that G is two complete graphs on n vertices connected by two edges. I got to this expression: $$2n^{2\left(n-2\right)}+2\left(n^{\left(n-2\right)}\sum_{i=0}^{n-2}\binom{n-2}{i}\left(1+i\right)^{\left(i-1\right)}\left(n-i-1\right)^{\left(n-i-3\right)}\right)$$ I know that this expression gives the correct result, however, I was told by my teacher that it is possible to express that number in closed form e.g. without the summation. However, I have yet to find a solution. How to edit a file in vi editor (arrow keys prints letters)? I am open a file in vi:  vi index.php   Here the problem is: when I press the down arrow and it prints 'B'. Why it prints 'B'? "I am going to have a walk" My teacher said "I am going to have a walk" today in class and to me it seems incorrect. Correct variants that I know are:    Going for a walk Going to take a walk Going to walk  ...   Is this correct? If so, why? LaTeX Editors/IDEs Logic Behind StackOverflow Question IDs java.lang.NoClassDefFoundError: org/apache/xpath/XPathAPI include svg images with the svg package Android Nougat .  It adds features such as multi-window support.  You can review the high-level changes at .  Of course, not all devices will get this update right away, even at release; others won't get it at all. Manufacturers and carriers often choose to add their own custom modifications, which tend to delay the official release.  When will each device get Nougat, either officially or unofficially, if ever?  See also: What does "proverbial" mean? I am trying to use a MERGE statement to insert or delete rows from a table, but I only want to act on a subset of those rows. The documentation for MERGE has a pretty strongly worded warning:     It is important to specify only the columns from the target table that are used for matching purposes. That is, specify columns from the target table that are compared to the corresponding column of the source table. Do not attempt to improve query performance by filtering out rows in the target table in the ON clause, such as by specifying AND NOT target_table.column_x = value. Doing so may return unexpected and incorrect results.   but this is exactly what it appears I have to do to make my MERGE work.  The data I have is a standard many-to-many join table of items to categories (e.g. which items are included in which categories) like so:  CategoryId   ItemId ==========   ====== 1            1 1            2 1            3 2            1 2            3 3            5 3            6 4            5   What I need to do is to effectively replace all rows in a specific category with a new list of items. My initial attempt to do this looks like this:  MERGE INTO CategoryItem AS TARGET USING (   SELECT ItemId FROM SomeExternalDataSource WHERE CategoryId = 2 ) AS SOURCE ON SOURCE.ItemId = TARGET.ItemId AND TARGET.CategoryId = 2 WHEN NOT MATCHED BY TARGET THEN     INSERT ( CategoryId, ItemId )     VALUES ( 2, ItemId ) WHEN NOT MATCHED BY SOURCE AND TARGET.CategoryId = 2 THEN     DELETE ;   This appears to be working in my tests, but I am doing exactly what MSDN explicitly warns me not to do. This makes me concerned that I will run into unexpected problems later on, but I cannot see any other way to make my MERGE only affect rows with the specific field value (CategoryId = 2) and ignore rows from other categories.  Is there a "more correct" way to achieve this same result? And what are the "unexpected or incorrect results" that MSDN is warning me about? Continuous function positive at a point is positive in a neighborhood of that point Pretty much the problem asks if a function is continuous at the point $c$ and $f(c) &gt; 0$ then there exists a $d &gt; 0$ such that $\forall x$, $f(x) &gt; 0$ with $|x-c| &lt; d$.   I can understand what the problem means. That if a function is positive at a point then there is another point that's really close that'll also be positive. I can not prove this in a formal way though. I've tried using the intermediate value theorem and I do not know hot to implement it. Any ideas? Proving $\lim_{n\to\infty} a^{\frac{1}{n}}=1$ by definition of limit What is the longest word you can come up with that the letters are all in alphabetical order? It's Friday again, how about some fun to get us into the weekend?  What is the longest word you can come up with for which all the letters in that word are in alphabetical order?   Rules:   English words only    Can't be a name of a place, person or other proper noun.   if it contains the same letter twice in a row, that does not disqualify it.   No fair looking it up on Google!   Update: One more rule to help you guys out.   The word can be in either ascending or descending alphabetical order. Is there a workaround to make CSS classes with names that start with numbers valid? /review tab not accessible on a private beta Who turned on the lightsaber? Spoilers for The Last Jedi:      Just before Snoke is slain,   he narrates Kylo Ren's thoughts/feelings (saying things like "he turns the lightsaber towards his enemy" and so on) we see the Skywalker lightsaber being manipulated through the Force to point towards and then slay Snoke. My question is, do we know for sure who was using to Force to use the Skywalker lightsaber in this scene?   It could have been   A) Kylo Ren was turning igniting the Skywalker lightsaber with the Force. Snoke assumed the thoughts/feelings he was sensing were directed at Rey but they weren't.   Or... B) Snoke was so preoccupied with Kylo's thoughts that he wasn't paying any attention to Rey's thoughts. Rey takes advantage of this and uses the Force to turn and ignite the Skywalker lightsaber to slay Snoke. This option is reinforced by the fact that  1) the Skywalker lightsaber then zooms into Rey's hand, not Kylo's.  2) after the ensuing scuffle, Kylo Ren reveals that he hasn't switched sides; he is still a believer in the First Order.  3) Kylo Ren even tells Hux that Rey slew Snoke. As expected, Nvidia drivers have reduced my customizations. I can't login to Unity 3D session. I can't find any content to help me to uninstall the driver and I don't know what to do as I have never uninstalled them before. fontenc changes sans serif bold font in KOMA-script Consider the following MWE:  \documentclass{article} %\usepackage[T1]{fontenc}  \begin{document}  \textbf{\textsf{Some text}}  \end{document}   The output of the above code is     and doesn't change if I uncomment the line  %\usepackage[T1]{fontenc}   Consider now the following MWE with scrartcl class instead of article:  \documentclass{scrartcl} %\usepackage[T1]{fontenc}  \begin{document}  \section{A section} \textsf{Some text} \end{document}      Uncommenting the line  %\usepackage[T1]{fontenc}   you get    As you can see, the sans serif font of the title is less  bold than without fontenc, while the normal text is not changed.  Does fontenc, combined with a KOMA-script class, load a different sans serif font, but only for bold face? How to show that for all k, $k! \ge (k/2)^{k/2}$