why is the return keyword not required in expression bodied methods Looking at expression bodied methods, I am trying to understand why the return keyword is not used. For example with public int GetAge() { return this.Age; }  I would have expected public int GetAge() =&gt; return this.Age;  as opposed to the correct public int GetAge() =&gt; this.Age;  Why is the return keyword not required/allowed in this case?
Expression Versus Statement I'm asking with regards to c#, but I assume its the same in most other languages.  Does anyone have a good definition of expressions and statements and what the differences are?
How do I theme a webform? In Harry Potter and the Deathly Hallows, when Voldemort tries to kill Harry Potter and Harry Potter travel to the Deathly hallows, that is, Kings Cross Station and he later comes back. There it has been mentioned that Voldemort had also fallen down and Bellatrix tried to support him to stand up as if she has some affection towards him.  “My Lord . . . my Lord . . . ” It was Bellatrix’s voice, and she spoke as if to a lover.  Is it true that Bellatrix Lestrange had some affection towards Voldemort? Meaning of $\int \phi^\dagger \hat A \psi \:\mathrm dx$ While analysing a problem in quantum Mechanics, I realized that I don't fully understand the physical meanings of certain integrals. I have been interpreting:    $\int \phi^\dagger \hat A \psi \:\mathrm dx$  as "(square root of) probability that a particle with state $|\psi\rangle$ will collapse to a state $|\phi\rangle$ when one tries to observe the observable corresponding to $\hat A$" $\int \phi^\dagger  \psi \:\mathrm dx$ as "(square root of) probability that a particle with state $|\psi\rangle$ will collapse to a state $|\phi\rangle$".   All integrals are over all space here, and all $\phi$s and $\psi$s are normalized.  Now, I realize that  interpretation of the first integral doesn't really make sense when put side by side with the second one.   For example, when $|\phi\rangle$ is an eigenstate of $\hat A$, I get two different expressions for "the square root of probability that one will get the corresponding eigenvalue of $\psi$ when one tries to observe the observable corresponding to $\hat A$". As far as I can tell, $\int \phi^\dagger \hat A \psi \:\mathrm dx \neq\int \phi^\dagger  \psi \:\mathrm dx $, even if $|\phi\rangle$ is an eigenstate of $\hat A$. I am inclined to believe that the second integral is the correct answer here (it comes naturally when you split $|\psi\rangle$ into a linear combination of basis vectors). But I am at a loss as to the interpretation of the first integral.  So, my question is, what are the physical interpretations of $\int \phi^\dagger \hat A \psi \:\mathrm dx$ and $\int \phi^\dagger  \psi \:\mathrm dx$?  (While I am familiar with the bra-ket notation, I have not used it in this question as I don't want to confuse myself further. Feel free to use it in your answer, though) How do exchanges match limit orders? Say a security has been trading at under $20.10, and there are limit orders selling at $20.10 and $20.21. Then Simon issues a limit order to buy at $20.21. According to , Simon would end up buying shares at $20.10.  Why does the exchange favor the buyer here?  I.e., why does the transaction execute at the seller's limit of $20.10 instead of the buyer's limit of $20.21?  (I.e., why don't Inara/River get to sell at $20.21 / above their limit, but Simon gets to buy at $20.10 / below his limit?)  Is the example flawed?  If it makes a difference, I'm mainly curious about NASDAQ and NYSE.  I tried Googling for specs (e.g. ), but couldn't find anything.  Only found that some  implementation executes the average of the buy/ask.  Just curious how the system works. How can I chain implicits in Scala? Since multiple inheritance is bad (it makes the source more complicated) C# does not provide such a pattern directly. But sometimes it would be helpful to have this ability. For instance I'm able to implement the missing multiple inheritance pattern using interfaces and three classes like that: public interface IFirst { void FirstMethod(); } public interface ISecond { void SecondMethod(); }  public class First:IFirst  {      public void FirstMethod() { Console.WriteLine(&quot;First&quot;); }  }  public class Second:ISecond  {      public void SecondMethod() { Console.WriteLine(&quot;Second&quot;); }  }  public class FirstAndSecond: IFirst, ISecond {     First first = new First();     Second second = new Second();     public void FirstMethod() { first.FirstMethod(); }     public void SecondMethod() { second.SecondMethod(); } }  Every time I add a method to one of the interfaces I need to change the class FirstAndSecond as well. Is there a way to inject multiple existing classes into one new class like it is possible in C++? Maybe there is a solution using some kind of code generation? Or it may look like this (imaginary c# syntax): public class FirstAndSecond: IFirst from First, ISecond from Second { }  So that there won't be a need to update the class FirstAndSecond when I modify one of the interfaces.  EDIT Maybe it would be better to consider a practical example: You have an existing class (e.g. a text based TCP client based on ITextTcpClient) which you do already use at different locations inside your project.  Now you feel the need to create a component of your class to be easy accessible for windows forms developers. As far as I know you currently have two ways to do this:  Write a new class that is inherited from components and implements the interface of the TextTcpClient class using an instance of the class itself as shown with FirstAndSecond.  Write a new class that inherits from TextTcpClient and somehow implements IComponent (haven't actually tried this yet).   In both cases you need to do work per method and not per class. Since you know that we will need all the methods of TextTcpClient and Component it would be the easiest solution to just combine those two into one class. To avoid conflicts this may be done by code generation where the result could be altered afterwards but typing this by hand is a pure pain in the ass. I  as unclear what you're asking after receiving flags on it in the moderator queue.   Once I did that, the text for the question title in the moderator queue changed from:     How to use handler to display images from database without passing ID in querystring?    to     How to use handler to display images from database without passing ID in querystring? [undefined more votes needed]    The text on the main page has stayed consistent with the new 'on hold' verbiage, however.  Here's a screenshot: Fiction novel or movie about sentient dinosaurs I remember parts of a story about some researchers finding a society of sentient dinosaurs. I believe they lived underground. From what I recall there were some steam punk elements and I think crystals were important.  From what I recall (this might be wrong) there was a book and also a movie about that story.  In the process, humans lived with these dinosaurs. I am not sure if that was like that from the beginning or if that happened later.  Any idea what that story might be? What is going on with pgfpages and page labels? I’m using a feature of beamer that shows notes beside slides, but the page numbers that are coming out are crazy, making it impossible to extract specific slides into other documents with \includegraphics[page=n]{presentation.pdf}.  For example, in this MWE, there are two frames that are each 1 slide, and then one frame that is four slides. The PDF page labels that show up in Acrobat are, as indicated, 2, 3, 3, 3, 3, and 7. It starts at page 2 instead of 1, and then there are four page 3s, but they don’t even all belong to the same frame!  \documentclass{beamer} \usepackage{pgfpages}  \setbeameroption{show notes on second screen=left} \setbeamertemplate{note page}{frame \insertframenumber \\ \insertnote} \def\pg#1{pgfpages says this is page #1 but it is really page \arabic{page}}  \begin{document}  \setcounter{page}{0}  \frame{hi \note{\pg{2}}}  \frame{there \note{\pg{3}}}  \frame{how \pause are \pause you \pause today \note&lt;1-3&gt;{\pg{3}} \note&lt;4&gt;{\pg{7}}}  \end{document}   Here’s what the output looks like:    I know that the manual says, “pgfpages will produce wrong page numbers in the .aux file” and gives a manual workaround. But the page counter still works, so shouldn’t there be some way to pass that through to the PDF? I’d like to fix this, but don’t know where to start. Specifically, when the manual says that “TeX instantiates the page numbers when writing an .aux file only when the physical page is shipped out,” what exactly is it talking about? Where is the source code for that? pgfplots from file: search path, looking for \graphicspath equivalent Is there a way to enable/disable a wireless network interface via the command line (so I can put it in a bat file)?  When I'm in the office I use a wired connection, but Windows still occasionally bugs me about my wireless connection not being connected (even though I turned off the option for notifying me when there's no connectivity).  I'm guessing the only way to stop it from bugging me is to disable the interface, but I'd rather not have to go into the network settings every time I need to do so.  I'd like to set up a bat file or a shortcut that I can use to enable/disable the wireless (preferably a single one that toggles the current state), and then just set up a keyboard shortcut for that.  I just have no idea how to do so from the command line. When to use Stateful session bean over Stateless session bean? Which form should be used for at­tribu­tive nouns like “stu­dent union”: sin­gu­lar or plu­ral, or pos­ses­sive sin­gu­lar or pos­ses­sive plu­ral? When should a noun that’s used at­tribu­tively to de­scribe an­other  noun be plu­ral, and when should it be sin­gu­lar?  And when should it be pos­ses­sive, like bak­er’s dozen and when should it be plu­ral pos­ses­sive, like farm­ers’ mar­ket?  In other words, why do we say teach­ers union rather than teacher  union?  And why do we say wed­ding plan­ner rather than wed­dings plan­ner?  Which of these vari­ants is or are cor­rect?        stu­dent union   stu­dents union   stu­den­t’s union   stu­dents’ union      What about com­mu­nity val­ues ver­sus com­mu­ni­ty’s val­ues?  Please note I am look­ing for a gen­eral rule or at least some tips.  These are only ex­am­ples.  Up­date: It seems even na­tive speak­ers fol­low their per­sonal  style to write such com­pound words. I won­der why in the IELTS lis­ten­ing sec­tion, the lan­guage learner has to write a spe­ci­fic form and there is no rule for this. Suppose the mean noon-time temperature for September days in San Diego is 24∘ and the standard deviation is 4.9. (Temperature in this problem is measured in degrees celsius)  On September 26, 1963, the all-time record of noon-time temperature in San Diego of 44∘ was hit. Assume the temperature distribution is symmetric around the mean, what is the Chebyshev bound for the probability of breaking (or tieing) this record?  I am having a hard time understanding this. Could someone explain to me how to do this? I am typing a command, I remember I have to check something, if I press Ctrl+U the command disappears and I can type something else, but then the command I was typing is not in the history.  Is there a way to recover that command, or a different shortcut that I can press to save somewhere the command? Option to hide rep/badges on the avatar block displayed of you Please have a look at this sentence:     We haven't gotten a lot of Finnish groups that we liked here at Bananas but I'm pretty happy with this four tracker from Helsinki, apparently recorded in the same place where the Ramones played in the 70's.     The first verb is in present perfect (up to now) and the second is in simple past tense. I don't understand the simple past for the second verb.  Why "like" is not in its present perfect form as the first verb is? I see a lot of interesting programs out there that can only be obtained by adding a "PPA" to the system but, if I'm understanding correctly, we should stay within the official "repositories" for adding software to our system.   Is there any way for a novice to know if a "PPA" is safe or if it should be avoided? What tips should the user know about when dealing with a PPA?. INNER JOIN ON vs WHERE clause If a function can only be defined implicitly does it have to be multivalued?