Do var Impact performance in C#
Will using 'var' affect performance?
Imagine that you want to develop a non-trivial end-user desktop (not web) application in Python. What is the best way to structure the project's folder hierarchy?  Desirable features are ease of maintenance, IDE-friendliness, suitability for source control branching/merging, and easy generation of install packages.  In particular:   Where do you put the source? Where do you put application startup scripts? Where do you put the IDE project cruft? Where do you put the unit/acceptance tests? Where do you put non-Python data such as config files? Where do you put non-Python sources such as C++ for pyd/so binary extension modules? Procedure for reducing the degrees of freedom of an arbitrary system Javascript: negative lookbehind equivalent? Is there a way to achieve the equivalent of a  in javascript regular expressions?  I need to match a string that does not start with a specific set of characters.  It seems I am unable to find a regex that does this without failing if the matched part is found at the beginning of the string.  Negative lookbehinds seem to be the only answer, but javascript doesn't have one.  EDIT: This is the regex that I would like to work, but it doesn't:  (?&lt;!([abcdefg]))m  So it would match the 'm' in 'jim' or 'm', but not 'jam' How do I remove a directory and all its contents? In bash all I know is that   rmdir directoryname   will remove the directory but only if it's empty. Is there a way to force remove subdirectories? Space before chapters and contents I am using LaTeX to write my dissertation, and I have realised that on the table of contents and on every chapter page, LaTeX leaves a lot of empty space.  What I mean is that lets say in the page where chapter 1 begins, from the top of the page until the chapter title there is much more vertical space than on any other page. The same goes with chapter 2 etc... and for contents page as well.   Can anybody help me to remove that space? Is there any mistake in my code or something like that? Is this a default of LaTeX?  the preamble is  \documentclass[12pt,twoside]{report} \pagestyle{plain} \usepackage{a4paper} \usepackage{setspace} \doublespacing  \usepackage{amssymb} \usepackage{amsmath}    I've tried the methods below, but none of them work properly. Easiest way to import access db (.accdb) into SQL Server 2016? I have a .accfb file from an access 2016 database and am trying to import this database into a SQL Server 2016 developer edition instance.   While I found posts online discussing using import/export data tools in SQL Server and also migration assistant for access, neither have worked out for me.   Does anyone know how to easily move a database from access 2016 to sql server 2016? More specifically an "accdb" file type?  All suggestions are greatly appreciated! Bump right-aligned text to next line iff no room Technically, NULL = NULL is False, by that logic no NULL is equal to any NULL and all NULLs are distinct. Shouldnt this imply that all NULLs are unique and a unique index should allow any number of NULLs? Why isn't Captain America worthy of Mjolnir? I haven't see the movie yet, but in the , we can see Cap trying to lift Mjolnir in the humorous scene where every Avenger gives it a try.  Mjolnir even moves just a tiny bit and at this very moment we see Thor's smile disappearing. This, of course, is intended as a humorous and lighthearted scene.  But it got me thinking: why isn't Captain America worthy of Mjolnir? He seems to be the most "perfect" human being anyone can be: brave, not selfish, legitimate leader, prompt to sacrifice (as seen in the first movie, when he jumps on a fake grenade).  I ask this question in light of this very specific scene, but I'm interested in the Marvel Universe (and Marvel Cinematic Universe) as a whole. Maybe Captain America did wield Mjolnir once? Maybe he has some individual flaw I am not aware of that makes him unworthy? I have the value 25.00 in a float, but when I print it on screen it is 25.0000000. How can I display the value with only two decimal places? The web is littered with any number of pages () giving an existence and uniqueness proof that a pair of squares can be found summing to primes congruent to 1 mod 4 (and also that there are no such pairs for primes congruent to 3 mod 4).  However, none of the stuff I've read on the topic offers any help with actually efficiently finding (ie other than a straight search up to sqrt(p)) the concrete values of such squares.  What's the best way to actually find them ? I was wondering if there was any was I could right click inside any instance of a "Finder" window such that I have an option that says "Open Terminal Here". It would be really helpful. I don't have any knowledge in hardware and would like to know which RAM should I buy for my laptop.  How do I discover what RAM I need &amp; how much my machine can take?  I have a Razer Blade 15 (RZ09-02705F76) 2018 but don't know if there is a specific type or format of RAM that suits it and don't know where to find this information. Two  have been announced in LoL.  They have an ability that makes them be able to recall together.                                  What are the limits to this ability? Can the 'non-recaller' jump in at the last second and get some kind of instant recall?  Can somebody with the setup to get on PBE test it and tell us what are the limitations of this ability? How can I produce the text Word_one_two in LaTeX?  I tried:  Samp\_Dist\_Corr   But, it doesn't quite look right. Also, I want it in the typewriter font, so actually, I'm doing:  \texttt{Samp\_Dist\_Corr}   I find it looks a bit like the underscore is merging in to the bottom of the "D", but maybe it's just because of the typewriter D? How caret calculates R Squared From the training output below, it looks like R squared is not calculated by the traditional formula 1 - SSE/SST, since lower error rate has lower R squared. So how is it calculated?    colsample_bytree  min_child_weight  RMSE      Rsquared    0.4               3                 16963.39  0.8799191   0.4               5                 16813.24  0.8788395 How can I disable cloud-init? I have a fully-configured instance and an image from that for an autoscaling group. When autoscaling new instances from this image, it calls cloud-init. cloud-init changes the hostname and breaks fstab.  I want to prevent cloud-init from starting on instance launch. Horizontal splash distance of water "NG NS" on ticket after airport security My friend installed Windows 7 on his computer (upgrading from XP).  He wasn't sure if his processor supported x64 or not, so he installed the x86 version, just to be on the safe side.  After I looked it up, it turns out his processor does support x64, and now we want to upgrade.  The question is: is it possible to upgrade without completely re-installing the OS?  Can I? Or do I have to format the C: partition again?