This is a replication of the problem:  #include &lt;stdio.h&gt; #include &lt;stdint.h&gt; #include &lt;unistd.h&gt;  template &lt;typename T&gt; struct a_class {     // build an a_class instance     template &lt;typename U&gt;     static a_class a_builder() {         return a_class(sizeof(U));     }      // print out size     void print() {         printf("%zd\n", size_);     }  private:     a_class(ssize_t size) : size_(size) {}     ssize_t size_; };   template &lt;typename T&gt; void some_func() {     a_class&lt;T&gt; a = a_class&lt;T&gt;::a_builder&lt;uint32_t&gt;();     a.print(); }   int main() {     some_func(); }   Under g++ 7.3.0 I get this error:   ╰─▸ g++ test.cc -o test test.cc: In function ‘void some_func()’: test.cc:26:50: error: expected primary-expression before ‘&gt;’ token      a_class&lt;T&gt; a = a_class&lt;T&gt;::a_builder&lt;uint32_t&gt;();                                                   ^ test.cc:26:52: error: expected primary-expression before ‘)’ token      a_class&lt;T&gt; a = a_class&lt;T&gt;::a_builder&lt;uint32_t&gt;();                                                     ^ test.cc: In function ‘int main()’: test.cc:32:15: error: no matching function for call to ‘some_func()’      some_func();                ^ test.cc:25:6: note: candidate: template&lt;class T&gt; void some_func()  void some_func() {       ^~~~~~~~~ test.cc:25:6: note:   template argument deduction/substitution failed: test.cc:32:15: note:   couldn't deduce template parameter ‘T’      some_func();                ^   Interestingly, if T is a concrete type:  void some_func() {     a_class&lt;int&gt; a = a_class&lt;int&gt;::a_builder&lt;uint32_t&gt;();     a.print(); }   Everything's fine.  Is there special syntax for this since it's a template context?
In templates, where and why do I have to put typename and template on dependent names? What exactly are dependent names anyway?    I have the following code:  template &lt;typename T, typename Tail&gt; // Tail will be a UnionNode too. struct UnionNode : public Tail {     // ...     template&lt;typename U&gt; struct inUnion {         // Q: where to add typename/template here?         typedef Tail::inUnion&lt;U&gt; dummy;      };     template&lt; &gt; struct inUnion&lt;T&gt; {     }; }; template &lt;typename T&gt; // For the last node Tn. struct UnionNode&lt;T, void&gt; {     // ...     template&lt;typename U&gt; struct inUnion {         char fail[ -2 + (sizeof(U)%2) ]; // Cannot be instantiated for any U     };     template&lt; &gt; struct inUnion&lt;T&gt; {     }; };   The problem I have is in the typedef Tail::inUnion&lt;U&gt; dummy line. I'm fairly certain that inUnion is a dependent name, and VC++ is quite right in choking on it. I also know that I should be able to add template somewhere to tell the compiler that inUnion is a template-id. But where exactly? And should it then assume that inUnion is a class template, i.e. inUnion&lt;U&gt; names a type and not a function?
A finite sum involving the binomial coefficients and the harmonic numbers Game resource timers - general implementation I'm interested in understanding how resource generation timers work on many of the mmorts type games out there. I can't wrap my head exactly around how the timers are synched with servers, especially with multiple users. If I need to provide more details, please let me know.  Thanks! I'm runing 15.04 on a dell xps 13 bluetooth recognises devices when i  try to add them but won't let me connect to them Here is the results from my terminal.  ~ $ uname -a; lspci -nnk | grep -iA2 net; lsusb; dmesg | grep -i bluetooth; dmesg | grep -i firmware; lsmod | grep bluetooth  Linux aaron-XPS-13 3.19.0-15-generic #15-Ubuntu SMP Thu Apr 16 23:32:37 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux 02:00.0 Network controller [0280]: Broadcom Corporation BCM4352 802.11ac Wireless Network Adapter [14e4:43b1] (rev 03)     Subsystem: Dell Device [1028:0019]     Kernel driver in use: wl Bus 003 Device 002: ID 8087:8001 Intel Corp.  Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 0bda:5682 Realtek Semiconductor Corp.  Bus 001 Device 002: ID 0a5c:216f Broadcom Corp.  Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub [    8.164048] Bluetooth: Core ver 2.20 [    8.164065] Bluetooth: HCI device and connection manager initialized [    8.164069] Bluetooth: HCI socket layer initialized [    8.164073] Bluetooth: L2CAP socket layer initialized [    8.164079] Bluetooth: SCO socket layer initialized [    8.353160] bluetooth hci0: Direct firmware load for brcm/BCM20702A0-0a5c-216f.hcd failed with error -2 [    8.353166] Bluetooth: hci0: BCM: patch brcm/BCM20702A0-0a5c-216f.hcd not found [   20.289452] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [   20.289455] Bluetooth: BNEP filters: protocol multicast [   20.289459] Bluetooth: BNEP socket layer initialized [   20.310897] Bluetooth: RFCOMM TTY layer initialized [   20.310907] Bluetooth: RFCOMM socket layer initialized [   20.310912] Bluetooth: RFCOMM ver 1.11 [  886.399085] Bluetooth: hci0 urb ffff8800d8c15e40 failed to resubmit (2) [  895.471190] Bluetooth: hci0: BCM: patching hci_ver=06 hci_rev=1000 lmp_ver=06 lmp_subver=220e [  896.113983] Bluetooth: hci0: BCM: firmware hci_ver=06 hci_rev=1624 lmp_ver=06 lmp_subver=220e [    8.353160] bluetooth hci0: Direct firmware load for brcm/BCM20702A0-0a5c-216f.hcd failed with error -2 [  896.113983] Bluetooth: hci0: BCM: firmware hci_ver=06 hci_rev=1624 lmp_ver=06 lmp_subver=220e bluetooth             491520  22 bnep,btusb,rfcomm ~ $ How can I switch between keyboard layouts by pressing a keyboard shortcut like on Windows? Possible Duplicate:          On Windows I am able to switch between keyboard layouts by pressing Alt+Shift. Is there a similar keyboard shortcut in Ubuntu? What do the brackets around processes mean? $ ps -Awwo pid,comm,args   PID COMMAND         COMMAND     1 init            /sbin/init     2 kthreadd        [kthreadd]     3 ksoftirqd/0     [ksoftirqd/0]     5 kworker/u:0     [kworker/u:0]     6 migration/0     [migration/0]     7 cpuset          [cpuset]     8 khelper         [khelper]     9 netns           [netns]    10 sync_supers     [sync_supers]    11 bdi-default     [bdi-default]    12 kintegrityd     [kintegrityd]    13 kblockd         [kblockd]    14 kacpid          [kacpid]    15 kacpi_notify    [kacpi_notify]    16 kacpi_hotplug   [kacpi_hotplug]    17 ata_sff         [ata_sff]    18 khubd           [khubd]   What do the brackets mean? Does args always return the full path to the process command (e.g. /bin/cat)? What's the best way to version CSS and JS URLs? Can someone please confirm the following? I have a C1/D visa. I worked as a flight attendant (currently unemployed) and entered the US numerous times, and also visited Mexico in December 2017.  I am planning on visiting Mexico again for 3 weeks in due course. Will the C1/D allow for me to transit in the US and visit Mexico or do I need a B1/B2 visa? I had issues with CBP before as it seems to be a very grey area.  According to the Mexican Consulate in South Africa, the type of visa is irrelevant. As long as it is multiple-entry, I am good to go.  Can someone please confirm, as I cannot get a solid answer from anyone?  Thank you! I want to use VBScript to catch errors and log them (ie on error "log something") then resume the next line of the script.  For example,   On Error Resume Next 'Do Step 1 'Do Step 2 'Do Step 3   When an error occurs on step 1, I want it to log that error (or perform other custom functions with it) then resume at step 2. Is this possible? and how can I implement it?  EDIT: Can I do something like this?   On Error Resume myErrCatch 'Do step 1 'Do step 2 'Do step 3  myErrCatch: 'log error Resume Next 3rd iterate of a continuous function equals identity function If $ f: \mathbb{R} \to \mathbb{R} $ is continuous, and $\forall x \in \mathbb{R} :\;(f \circ f \circ f)(x) = x  $, show that $ f(x) = x $.  The condition that $f$ is continuous on $\mathbb{R}$ is crucial for the proof. I can find functions such as $\displaystyle\frac{x-3}{x+1}$ that satisfies  $ (f \circ f \circ f)(x) = x $. I have tried to negate the conclusion to see if there's a contradiction, but got stuck. Don't let the association bonus be given away as bounties When a user with at least 200 rep on any Stack Exchange site registers a new account on another SE site, they immediately receive 100 rep on that site as an .  This is a deliberate feature to give users who are already familiar with how the SE platform and community works a bit of an extra boost (e.g. letting them upvote and comment immediately), and it's pretty much working as intended. What's probably not intended is that, currently, this bonus rep can be given away as . In fact, because awarding bounties currently requires only 75 rep, any user with 200+ rep on at least one site can join another site, receive the 100 rep bonus, and immediately award it all as a bounty to another user, without having to earn any actual rep on the site at all.  Not only does this seem contrary to the design intent of bounties (and of the association bonus), but it also seems ripe for potential abuse. (In fact, the only thing stopping a sockpuppet ring from gaining unlimited rep this way is the fact that the bounties would likely be sooner or later noticed by mods.) It's also possible for experienced users to (more or less) accidentally bounty their reputation so low that that they lose access to basic site features that they'd normally have due to the bonus.  Arguably, of course, this is entirely the user's own fault, but it can still be .  Also, this behavior , which currently require 110 rep to answer for users with the association bonus. The fix I'd like to suggest is simple:  If a user has been awarded the association bonus, don't let them award a bounty that would take their rep below 100.  Of course, it would still be possible for users with the bonus to drop below 100 rep via other means, e.g. by having their posts downvoted.  But they wouldn't be able to just give away this baseline rep to other users any more. Allow people to answer protected questions if they have earned at least some amount of combined SE rep The purpose of protected questions is, according to the message presented on such a question, "to prevent 'thanks!', 'me too!', or spam answers by new users." The more verbose  agrees on the purpose. And the  says this is why protected questions exist:     Some questions are protected because they are expected to attract   either spam or users -- often new users -- who may mistake the site as   a traditional forum, posting "noisy" answers such as "Thank you" or   "This worked for me" or "I'm also having this problem".   Considering this, shouldn't a user be able to answer protected questions if they have gained at least 10 rep on any stack exchange site? If they've already demonstrated one site that they are familiar enough with the SE Q/A format to not be a drive-by useless answerer, shouldn't that confidence in them carry over to other SE sites?  Or maybe at some level of combined SE rep this restriction should be waived. I find it silly that at 15k+ combined network rep, I'm unable to answer a protected question on a SE site I've just started using. The problem with reputation: does high reputation attract too many upvotes? It's not that I feel bitter when somebody else's answer is upvoted above my own, but it's when a user with a high rep answers a question and their answer seems to attract an immediate barrage of upvotes.  Now I'm not saying that these votes are always unwarranted, but by simply observing this behavior, I think the system seems flawed.    The concept of reputation (or at least one of the concepts) is to give users a sense of trust in the reputed user's answers.  But this should be trust, not blind faith.  I know that this problem doesn't exist for every question asked on SO, but it's definitely present.  I'm sure this is a contentious question, as it might seem overly critical, but does anybody else agree with me and, if so, does anybody have any thoughts on how this problem could be alleviated? It's a great shame when a new or less active user's answer is stifled by the reputation-rich user's answer. It would be similar to trying to be extremely careful or precise.   In French it would be "application", For example: "Qui est fait avec application".   Example usage:      John worked with ________. or ...it was done with _______. How to enable multiple logon remote desktop in Windows 7 Was Elrond, in Tolkien's opinion, more inherently powerful than Galadriel? I always thought it was the other way around, but then I read this (Letter 246):     "Of the others only Gandalf might be expected to master him – being an emissary of the Powers and a creature of the same order, an immortal spirit taking a visible physical form. In the 'Mirror of Galadriel', 1381, it appears that Galadriel conceived of herself as capable of wielding the Ring and supplanting the Dark Lord. If so, so also were the other guardians of the Three, especially Elrond. But this is another matter. It was part of the essential deceit of the Ring to fill minds with imaginations of supreme power."   This "especially Elrond" confuses me. I don´t think that Elrond is inherently more powerful than Galadriel, who is described as the greatest of the Noldor, except for Fëanor (and possibly even his equal).  A quote from Unfinished Tales says:     "...In this he (Tolkien) emphasized the commanding stature of   Galadriel already in Valinor, the equal if unlike endowments of   Fëanor; and it is said here that so far from joining in Fëanor's   revolt she was in every way opposed to him."   Furthermore,      "A queen she was of the woodland Elves, the wife of Celeborn of   Doriath, yet she herself was of the Noldor and remember the Day before   days in Valinor, and she was the mightiest and fairest (so even   fairer than Arwen I would guess) of all the Elves that remained in   Middle-earth."   (The Silmarillion, of the Rings of Power)  And again...     "Galadriel was the greatest of the Noldor, except Fëanor maybe, though   she was wiser than he, and her wisdom increased with the long years."   (the Shibboleth of Fëanor)  Restating it:     "These two kinsfolk (Fëanor and Galadriel), the greatest of the   Eldar in Valinor, were unfriends for ever." "Who together with the   greatest of all the Eldar, Luthien Tinuviel, daughter of Elu Thingol,   are the chief matter of the legends and histories of the Elves."   (Unfinished Tales)  The latter means that Luthien, Fëanor and Galadriel are the chief matter of the history and legends. It seems to me that Tolkien thought of those three as the creme de la creme of the elven crop.  Reading all that I have serious problems believing that Elrond could be superior to her. As great as Elrond is, descending from Melian, he is no equal of Fëanor, who is said to be the mightiest of all elves, and if Galadriel is his equal, then there is no way that Elrond would be mightier than her.  Maybe I just read this "especially Elrond" wrong; it could as well mean that especially Elrond was deceived into thinking that he could master the ring, because that was the deceit of the ring. And Tolkien said explicitly that only Gandalf could possibly master it.  So, what do you think? How to compute $\lim _{x\to 0}\frac{x\bigl(\sqrt{3e^x+e^{3x^2}}-2\bigr)}{4-(\cos x+1)^2}$? I have a problem with this limit, I don't know what method to use. I have no idea how to compute it. Is it possible to compute this limit with the McLaurin expansion? Can you explain the method and the steps used? Thanks. (I prefer to avoid to use L'Hospital's rule.)  $$\lim _{x\to 0}\frac{x\bigl(\sqrt{3e^x+e^{3x^2}}-2\bigr)}{4-(\cos x+1)^2}$$ Integration by partial fractions; how and why does it work? Could someone take me through the steps of decomposing  $$\frac{2x^2+11x}{x^2+11x+30}$$ into partial fractions?   More generally, how does one use partial fractions to compute integrals $$\int\frac{P(x)}{Q(x)}\,dx$$ of rational functions ($P(x)$ and $Q(x)$ are polynomials) ?    This question is asked in an effort to cut down on duplicates. See .  Also see . I am trying to write a VF page to list all the id and name columns from a custom object but found an error "List has more than 1 row" in the VF page.  Can anyone tell me what have I done wrong?  VF Page:  &lt;apex:page Controller="MP_controller" showHeader="false" sidebar="false"&gt;   &lt;apex:pageBlock&gt;      &lt;apex:pageBlockTable value="{! mp}" var="item"&gt;         &lt;apex:column value="{! item.id}"/&gt;         &lt;apex:column value="{! item.name}"/&gt;       &lt;/apex:pageBlockTable&gt;   &lt;/apex:pageBlock&gt; &lt;/apex:page&gt;   Apex controller  global with sharing class MP_controller {     public Merchant_Profile__c mp{get;set;}     public MP_controller(){         mp = [SELECT                  ID, name, Profile_account_name__c, Merchant_ID__c, Bank_Code__c, Country_Code__c,                 Currency_Code__c, Merchant_Level__c, Merchant_Type__c, MSO__c, Region__c,                 Retail_Products__c, Transaction_Mode__c, Created_Date__c, Date_Disabled__c, Date_Live__c,                 Merchant_Category_Code__c                FROM Merchant_Profile__c               WHERE Profile_Account_Name__c = '001O000000bQFnyIAG'];     } } Installing PHP 5.3 in Ubuntu 14.04 I've just installed Ubuntu 14.04 and am trying to install php 5.3. But when I run   apt-get install php5    it's installing php 5.5.9-1ubuntu4. I need to use php 5.3 in the system because the application I'm working on is built with php 5.3.   How can I achieve this? How do I boot to a command line interface instead of a GUI? Hi I have ubuntu server 10.04 installed and I also installed the following:  su aptitude install xorg xfce4 aptitude install &lt;name of GUI browser, I use firefox&gt; aptitude install gedit aptitude install gnome-terminal   Now when I restart the system it goes to the GUI login, what I am really after is a system that loads the CLI by default and then I can use startx to load the GUI when really necessary. I am trying to learn CLI but I would like to retain access to the GUI for now. And, how can I switch between CLI and GUI anytime?