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  • Is it possible to get a google voice number without already having a phone number?

    - by boost
    I'm sorry if this is the wrong place to post this, but I couldn't find a more suitable website in the stackexchange network. I currently have no phone number; I can make outgoing calls via the widget in gmail, but I cannot receive calls (as far as I know). I know that you can set up a google voice number to forward to google chat, and this is exactly what I want. The problem is, I can't get a google voice number in the first place, because it first requires that I have an existing phone number, even if I wouldn't use it. So, it is possible to skip providing an existing phone number, and just get a google voice number that forwards to google chat? Alternatively, is there any free phone service that can be used without a phone and lets you receive calls from any number? I realize I'm kind of asking for free candy, but, if it's out there, I'd be a fool

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  • Online Content Distribution is a Valuable SEO Tool

    Online content distribution is quite possibly one of the best and easiest ways to boost your search engine rankings if done properly. It is quite common however to overlook the importance this strategy can play in our optimization efforts. Read on to see 5 ways in which using content can boost your SEO efforts leading to even more exposure and traffic.

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  • What would a new web development tool need to succeed?

    - by boost
    If one wanted to bring a new web development tool to market, what would it have to be able to do that would differentiate it enough from all the others to attract people's attention? In what areas are all the other frameworks and languages falling down, such that if a new product addressed those issues, it would stand a chance of being adopted by significant user community?

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  • Compiling Gearman PHP Library for CentOS 5.8

    - by Andrew Ellis
    I've been trying to get Gearman compiled on CentOS 5.8 all afternoon. Unfortunately I am restricted to this version of CentOS by my CTO and how he has our entire network configured. I think it's simply because we don't have enough resources to upgrade our network... But anyways, the problem at hand. I have searched through Server Fault, Stack Overflow, Google, and am unable to locate a working solution. What I have below is stuff I have pieced together from my searching. Searches have told said to install the following via yum: yum -y install --enablerepo=remi boost141-devel libgearman-devel e2fsprogs-devel e2fsprogs gcc44 gcc-c++ To get the Boost headers working correctly I did this: cp -f /usr/lib/boost141/* /usr/lib/ cp -f /usr/lib64/boost141/* /usr/lib64/ rm -f /usr/include/boost ln -s /usr/include/boost141/boost /usr/include/boost With all of the dependancies installed and paths setup I then download and compile gearmand-1.1.2 just fine. wget -O /tmp/gearmand-1.1.2.tar.gz https://launchpad.net/gearmand/1.2/1.1.2/+download/gearmand-1.1.2.tar.gz cd /tmp && tar zxvf gearmand-1.1.2.tar.gz ./configure && make -j8 && make install That works correctly. So now I need to install the Gearman library for PHP. I have attempted through PECL and downloading the source directly, both result in the same error: checking whether to enable gearman support... yes, shared not found configure: error: Please install libgearman What I don't understand is I installed the libgearman-devel package which also installed the core libgearman. The installation installs libgearman-devel-0.14-3.el5.x86_64, libgearman-devel-0.14-3.el5.i386, libgearman-0.14-3.el5.x86_64, and libgearman-0.14-3.el5.i386. Is it possible the package version is lower than what is required? I'm still poking around with this, but figured I'd throw this up to see if anyone has a solution while I continue to research a fix. Thanks!

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  • creating a color coded time chart using colorbar and colormaps in python

    - by Rusty
    I'm trying to make a time tracking chart based on a daily time tracking file that I used. I wrote code that crawls through my files and generates a few lists. endTimes is a list of times that a particular activity ends in minutes going from 0 at midnight the first day of the month to however many minutes are in a month. labels is a list of labels for the times listed in endTimes. It is one shorter than endtimes since the trackers don't have any data about before 0 minute. Most labels are repeats. categories contains every unique value of labels in order of how well I regard that time. I want to create a colorbar or a stack of colorbars (1 for eachday) that will depict how I spend my time for a month and put a color associated with each label. Each value in categories will have a color associated. More blue for more good. More red for more bad. It is already in order for the jet colormap to be right, but I need to get desecrate color values evenly spaced out for each value in categories. Then I figure the next step would be to convert that to a listed colormap to use for the colorbar based on how the labels associated with the categories. I think this is the right way to do it, but I am not sure. I am not sure how to associate the labels with color values. Here is the last part of my code so far. I found one function to make a discrete colormaps. It does, but it isn't what I am looking for and I am not sure what is happening. Thanks for the help! # now I need to develop the graph import numpy as np from matplotlib import pyplot,mpl import matplotlib from scipy import interpolate from scipy import * def contains(thelist,name): # checks if the current list of categories contains the one just read for val in thelist: if val == name: return True return False def getCategories(lastFile): ''' must determine the colors to use I would like to make a gradient so that the better the task, the closer to blue bad labels will recieve colors closer to blue read the last file given for the information on how I feel the order should be then just keep them in the order of how good they are in the tracker use a color range and develop discrete values for each category by evenly spacing them out any time not found should assume to be sleep sleep should be white ''' tracker = open(lastFile+'.txt') # open the last file # find all the categories categories = [] for line in tracker: pos = line.find(':') # does it have a : or a ? if pos==-1: pos=line.find('?') if pos != -1: # ignore if no : or ? name = line[0:pos].strip() # split at the : or ? if contains(categories,name)==False: # if the category is new categories.append(name) # make a new one return categories # find good values in order of last day newlabels=[] for val in getCategories(lastDay): if contains(labels,val): newlabels.append(val) categories=newlabels # convert discrete colormap to listed colormap python for ii,val in enumerate(labels): if contains(categories,val)==False: labels[ii]='sleep' # create a figure fig = pyplot.figure() axes = [] for x in range(endTimes[-1]%(24*60)): ax = fig.add_axes([0.05, 0.65, 0.9, 0.15]) axes.append(ax) # figure out the colors to use # stole this function to make a discrete colormap # http://www.scipy.org/Cookbook/Matplotlib/ColormapTransformations def cmap_discretize(cmap, N): """Return a discrete colormap from the continuous colormap cmap. cmap: colormap instance, eg. cm.jet. N: Number of colors. Example x = resize(arange(100), (5,100)) djet = cmap_discretize(cm.jet, 5) imshow(x, cmap=djet) """ cdict = cmap._segmentdata.copy() # N colors colors_i = np.linspace(0,1.,N) # N+1 indices indices = np.linspace(0,1.,N+1) for key in ('red','green','blue'): # Find the N colors D = np.array(cdict[key]) I = interpolate.interp1d(D[:,0], D[:,1]) colors = I(colors_i) # Place these colors at the correct indices. A = zeros((N+1,3), float) A[:,0] = indices A[1:,1] = colors A[:-1,2] = colors # Create a tuple for the dictionary. L = [] for l in A: L.append(tuple(l)) cdict[key] = tuple(L) # Return colormap object. return matplotlib.colors.LinearSegmentedColormap('colormap',cdict,1024) # jet colormap goes from blue to red (good to bad) cmap = cmap_discretize(mpl.cm.jet, len(categories)) cmap.set_over('0.25') cmap.set_under('0.75') #norm = mpl.colors.Normalize(endTimes,cmap.N) print endTimes print labels # make a color list by matching labels to a picture #norm = mpl.colors.ListedColormap(colorList) cb1 = mpl.colorbar.ColorbarBase(axes[0],cmap=cmap ,orientation='horizontal' ,boundaries=endTimes ,ticks=endTimes ,spacing='proportional') pyplot.show()

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  • ld: symbol(s) not found with OpenSSL (libssl)

    - by Benjamin
    Hi all, I'm trying to build TorTunnel on my mac. I've successfully installed the Boost library and its development files. TorTunnel also requires the OpenSSL and its development files. I've got them installed in /usr/lib/libssl.dylib and /usr/include/openssl/. When I run the make command this is the error i'm getting: g++ -ggdb -g -O2 -lssl -lboost_system-xgcc42-mt-1_38 -o torproxy TorProxy.o HybridEncryption.o Connection.o Cell.o Directory.o ServerListing.o Util.o Circuit.o CellEncrypter.o RelayCellDispatcher.o CellConsumer.o ProxyShuffler.o CreateCell.o CreatedCell.o TorTunnel.o SocksConnection.o Network.o Undefined symbols: "_BN_hex2bn", referenced from: Circuit::initializeDhParameters() in Circuit.o "_BN_free", referenced from: Circuit::~Circuit()in Circuit.o Circuit::~Circuit()in Circuit.o CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o "_DH_generate_key", referenced from: Circuit::initializeDhParameters() in Circuit.o "_PEM_read_bio_RSAPublicKey", referenced from: ServerListing::getOnionKey() in ServerListing.o "_BIO_s_mem", referenced from: Connection::initializeSSL() in Connection.o Connection::initializeSSL() in Connection.o "_DH_free", referenced from: Circuit::~Circuit()in Circuit.o "_BIO_ctrl_pending", referenced from: Connection::writeFromBuffer(boost::function)in Connection.o "_RSA_size", referenced from: HybridEncryption::encryptInSingleChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o HybridEncryption::encryptInHybridChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o HybridEncryption::encrypt(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o "_RSA_public_encrypt", referenced from: HybridEncryption::encryptInSingleChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o HybridEncryption::encryptInHybridChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o "_BN_num_bits", referenced from: CreateCell::CreateCell(unsigned short, dh_st*, rsa_st*)in CreateCell.o CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o CreatedCell::isValid() in CreatedCell.o "_SHA1", referenced from: CellEncrypter::expandKeyMaterial(unsigned char*, int, unsigned char*, int)in CellEncrypter.o "_BN_bn2bin", referenced from: CreateCell::CreateCell(unsigned short, dh_st*, rsa_st*)in CreateCell.o "_BN_bin2bn", referenced from: CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o "_DH_compute_key", referenced from: CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o "_BIO_new", referenced from: Connection::initializeSSL() in Connection.o Connection::initializeSSL() in Connection.o "_BIO_new_mem_buf", referenced from: ServerListing::getOnionKey() in ServerListing.o "_AES_ctr128_encrypt", referenced from: HybridEncryption::AES_encrypt(unsigned char*, int, unsigned char*, unsigned char*, int)in HybridEncryption.o CellEncrypter::aesOperate(Cell&, aes_key_st*, unsigned char*, unsigned char*, unsigned int*)in CellEncrypter.o "_BIO_read", referenced from: Connection::writeFromBuffer(boost::function)in Connection.o "_SHA1_Update", referenced from: CellEncrypter::calculateDigest(SHAstate_st*, RelayCell&, unsigned char*)in CellEncrypter.o CellEncrypter::initKeyMaterial(unsigned char*)in CellEncrypter.o CellEncrypter::initKeyMaterial(unsigned char*)in CellEncrypter.o "_SHA1_Final", referenced from: CellEncrypter::calculateDigest(SHAstate_st*, RelayCell&, unsigned char*)in CellEncrypter.o "_DH_size", referenced from: CreatedCell::getKeyMaterial(unsigned char**, unsigned char**)in CreatedCell.o "_DH_new", referenced from: Circuit::initializeDhParameters() in Circuit.o "_BIO_write", referenced from: Connection::readIntoBufferComplete(boost::function, boost::system::error_code const&, unsigned long)in Connection.o "_RSA_free", referenced from: Circuit::~Circuit()in Circuit.o "_BN_dup", referenced from: Circuit::initializeDhParameters() in Circuit.o Circuit::initializeDhParameters() in Circuit.o "_BN_new", referenced from: Circuit::initializeDhParameters() in Circuit.o Circuit::initializeDhParameters() in Circuit.o "_SHA1_Init", referenced from: CellEncrypter::CellEncrypter()in CellEncrypter.o CellEncrypter::CellEncrypter()in CellEncrypter.o "_RAND_bytes", referenced from: HybridEncryption::encryptInHybridChunk(unsigned char*, int, unsigned char**, int*, rsa_st*)in HybridEncryption.o Util::getRandomId() in Util.o "_AES_set_encrypt_key", referenced from: HybridEncryption::AES_encrypt(unsigned char*, int, unsigned char*, unsigned char*, int)in HybridEncryption.o CellEncrypter::initKeyMaterial(unsigned char*)in CellEncrypter.o CellEncrypter::initKeyMaterial(unsigned char*)in CellEncrypter.o "_BN_set_word", referenced from: Circuit::initializeDhParameters() in Circuit.o "_RSA_new", referenced from: ServerListing::getOnionKey() in ServerListing.o ld: symbol(s) not found collect2: ld returned 1 exit status make: *** [torproxy] Error 1 Any idea how I could fix it?

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  • Who does non-decimal bignums with floating radix point?

    - by boost
    Nice as the Tcl libraries math::bignum and math::bigfloat are, the middle ground between the two needs to be addressed. Namely, bignums which are in different radices and have a radix point. At present math::bignum only handles integers (afaict) and math::bigfloat won't let you specify different radices to math::bigfloat::fromstr (ditto). Does anyone know of a library, for any of the major scripting languages (e.g. Tcl, Perl, Python, Ruby, Lua) or less major ones (newLISP for example), which implements bignums in different radices with handling for radix point?

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  • How do you change the subdocument location in a Word 2007 master document programmatically?

    - by boost
    We have had the unenviable happen: various master documents refer to sub-documents that are no longer where they used to be due to a directory renaming. Is there a programmatic way of tweaking the HYPERLINK field without losing the master/sub-document relationship? I've got this far ... Sub FixyaLinks() Dim s 'As String Dim i As Long Dim bTrackRevFlag As Boolean Dim bShowRevFlag As Boolean bTrackRevFlag = ActiveDocument.TrackRevisions bShowRevFlag = ActiveDocument.ShowRevisions ActiveDocument.TrackRevisions = False ActiveDocument.ShowRevisions = False For i = 1 To ActiveDocument.Fields.Count s = ActiveDocument.Fields.Item(i).Code.Text If InStr(s, "CURRICULUM\\NEW") Then s = Replace(s, "NEW Foundation Units-in developing", "Foundation Programme Units") ActiveDocument.Fields.Item(i).Code.Text = s End If Next ActiveDocument.TrackRevisions = bTrackRevFlag ActiveDocument.ShowRevisions = bShowRevFlag End Sub It bombs on ActiveDocument.Fields.Item(i).Code.Text = s, with an error 5686 ("The operation cannot be completed because the Track Changes option in the master document does not match the option the the subdocument. Make the Track Changes option the same in the master document and subdocument.") However, I'm not entirely sure what that means. Ideas anyone?

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  • What is wrong with this recursive Windows CMD script? It won't do Ackermann properly

    - by boost
    I've got this code that I'm trying to get to calculate the Ackermann function so that I can post it up on RosettaCode. It almost works. I thought maybe there'd be a few batch file wizards on StackOverflow. ::echo off set depth=0 :ack if %1==0 goto m0 if %2==0 goto n0 :else set /a n=%2-1 set /a depth+=1 call :ack %1 %n% set t=%errorlevel% set /a depth-=1 set /a m=%1-1 set /a depth+=1 call :ack %m% %t% set t=%errorlevel% set /a depth-=1 if %depth%==0 ( exit %t% ) else ( exit /b %t% ) :m0 set/a n=%2+1 if %depth%==0 ( exit %n% ) else ( exit /b %n% ) :n0 set /a m=%1-1 set /a depth+=1 call :ack %m% %2 set t=%errorlevel% set /a depth-=1 if %depth%==0 ( exit %t% ) else ( exit /b %t% ) I use this script to test it @echo off cmd/c ackermann.cmd %1 %2 echo Ackermann of %1 %2 is %errorlevel% A sample output, for Test 1 1, gives: >test 1 1 >set depth=0 >if 1 == 0 goto m0 >if 1 == 0 goto n0 >set /a n=1-1 >set /a depth+=1 >call :ack 1 0 >if 1 == 0 goto m0 >if 0 == 0 goto n0 >set /a m=1-1 >set /a depth+=1 >call :ack 0 0 >if 0 == 0 goto m0 >set/a n=0+1 >if 2 == 0 (exit 1 ) else (exit /b 1 ) >set t=1 >set /a depth-=1 >if 1 == 0 (exit 1 ) else (exit /b 1 ) >set t=1 >set /a depth-=1 >set /a m=1-1 >set /a depth+=1 >call :ack 0 1 >if 0 == 0 goto m0 >set/a n=1+1 >if 1 == 0 (exit 2 ) else (exit /b 2 ) >set t=2 >set /a depth-=1 >if 0 == 0 (exit 2 ) else (exit /b 2 ) Ackermann of 1 1 is 2

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  • What tasks aren't easy for PHP, ColdFusion and ASP?

    - by boost
    PHP, ColdFusion, and ASP (among many others) are usually sold on their strengths. What are their weaknesses? If one were to develop a niche product to handle the things that these products weren't so good at, what should it focus on? EDIT I'm trying to figure out what things PHP etc are bad at. They're all good at doing the nuts and bolts stuff, if one is looking with a bottom-to-top mindset. I'm thinking a little more globally, more top-to-bottom; what's difficult to achieve in PHP/ASP/CF without thousands of lines of code and twenty minutes of server time? EDIT Suppose company A comes up to you and says, "We want you to do x in PHP." What values of x will cause you to say, "Forget it, buddy, no one in their right mind would use PHP for that"? (swap PHP in the above quote for your favourite tool) EDIT Have we got to the point where everyone's needs can be met with PHP frameworks, Rails and ... er ... Java?

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  • How do you calculate div and mod of floating point numbers?

    - by boost
    In Perl, the % operator seems to assume integers. For instance: sub foo { my $n1 = shift; my $n2 = shift; print "perl's mod=" . $n1 % $n2, "\n"; my $res = $n1 / $n2; my $t = int($res); print "my div=$t", "\n"; $res = $res - $t; $res = $res * $n2; print "my mod=" . $res . "\n\n"; } foo( 3044.952963, 7.1 ); foo( 3044.952963, -7.1 ); foo( -3044.952963, 7.1 ); foo( -3044.952963, -7.1 ); gives perl's mod=6 my div=428 my mod=6.15296300000033 perl's mod=-1 my div=-428 my mod=6.15296300000033 perl's mod=1 my div=-428 my mod=-6.15296300000033 perl's mod=-6 my div=428 my mod=-6.15296300000033 Now as you can see, I've come up with a "solution" already for calculating div and mod. However, what I don't understand is what effect the sign of each argument should have on the result. Wouldn't the div always be positive, being the number of times n2 fits into n1? How's the arithmetic supposed to work in this situation?

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  • Mutating Programming Language?

    - by MattiasK
    For fun I was thinking about how one could build a programming language that differs from OOP and came up with this concept. I don't have a strong foundation in computer science so it might be common place without me knowing it (more likely it's just a stupid idea :) I apologize in advance for this somewhat rambling question :) Anyways here goes: In normal OOP methods and classes are variant only upon parameters, meaning if two different classes/methods call the same method they get the same output. My, perhaps crazy idea, is that the calling method and class could be an "invisible" part of it's signature and the response could vary depending on who call's an method. Say that we have a Window object with a Break() method, now anyone (who has access) could call this method on Window with the same result. Now say that we have two different objects, Hammer and SledgeHammer. If Break need to produce different results based on these we'd pass them as parameters Break(IBluntObject bluntObject) With a mutating programming language (mpl) the operating objects on the method would be visible to the Break Method without begin explicitly defined and it could adopt itself based on them). So if SledgeHammer calls Window.Break() it would generate vastly different results than if Hammer did so. If OOP classes are black boxes then MPL are black boxes that knows who's (trying) to push it's buttons and can adapt accordingly. You could also have different permission sets on methods depending who's calling them rather than having absolute permissions like public and private. Does this have any advantage over OOP? Or perhaps I should say, would it add anything to it since you should be able to simply add this aspect to methods (just give access to a CallingMethod and CallingClass variable in context) I'm not sure, might be to hard to wrap one's head around, it would be kinda interesting to have classes that adopted themselves to who uses them though. Still it's an interesting concept, what do you think, is it viable?

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  • Need help modifying C++ application to accept continuous piped input in Linux

    - by GreeenGuru
    The goal is to mine packet headers for URLs visited using tcpdump. So far, I can save a packet header to a file using: tcpdump "dst port 80 and tcp[13] & 0x08 = 8" -A -s 300 | tee -a ./Desktop/packets.txt And I've written a program to parse through the header and extract the URL when given the following command: cat ~/Desktop/packets.txt | ./packet-parser.exe But what I want to be able to do is pipe tcpdump directly into my program, which will then log the data: tcpdump "dst port 80 and tcp[13] & 0x08 = 8" -A -s 300 | ./packet-parser.exe Here is the script as it is. The question is: how do I need to change it to support continuous input from tcpdump? #include <boost/regex.hpp> #include <fstream> #include <cstdio> // Needed to define ios::app #include <string> #include <iostream> int main() { // Make sure to open the file in append mode std::ofstream file_out("/var/local/GreeenLogger/url.log", std::ios::app); if (not file_out) std::perror("/var/local/GreeenLogger/url.log"); else { std::string text; // Get multiple lines of input -- raw std::getline(std::cin, text, '\0'); const boost::regex pattern("GET (\\S+) HTTP.*?[\\r\\n]+Host: (\\S+)"); boost::smatch match_object; bool match = boost::regex_search(text, match_object, pattern); if(match) { std::string output; output = match_object[2] + match_object[1]; file_out << output << '\n'; std::cout << output << std::endl; } file_out.close(); } } Thank you ahead of time for the help!

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  • Specializing a class template constructor

    - by SilverSun
    I'm messing around with template specialization and I ran into a problem with trying to specialize the constructor based on what policy is used. Here is the code I am trying to get to work. #include <cstdlib> #include <ctime> class DiePolicies { public: class RollOnConstruction { }; class CallMethod { }; }; #include <boost/static_assert.hpp> #include <boost/type_traits/is_same.hpp> template<unsigned sides = 6, typename RollPolicy = DiePolicies::RollOnConstruction> class Die { // policy type check BOOST_STATIC_ASSERT(( boost::is_same<RollPolicy, DiePolicies::RollOnConstruction>::value || boost::is_same<RollPolicy, DiePolicies::CallMethod>::value )); unsigned m_die; unsigned random() { return rand() % sides; } public: Die(); void roll() { m_die = random(); } operator unsigned () { return m_die + 1; } }; template<unsigned sides> Die<sides, DiePolicies::RollOnConstruction>::Die() : m_die(random()) { } template<unsigned sides> Die<sides, DiePolicies::CallMethod>::Die() : m_die(0) { } ...\main.cpp(29): error C3860: template argument list following class template name must list parameters in the order used in template parameter list ...\main.cpp(29): error C2976: 'Die' : too few template arguments ...\main.cpp(31): error C3860: template argument list following class template name must list parameters in the order used in template parameter list Those are the errors I get in Microsoft Visual Studio 2010. I'm thinking either I can't figure out the right syntax for the specialization, or maybe it isn't possible to do it this way.

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  • Detecting const-ness of nested type

    - by Channel72
    Normally, if I need to detect whether a type is const I just use boost::is_const. However, I ran into trouble when trying to detect the const-ness of a nested type. Consider the following traits template, which is specialized for const types: template <class T> struct traits { typedef T& reference; }; template <class T> struct traits<const T> { typedef T const& reference; }; The problem is that boost::is_const doesn't seem to detect that traits<const T>::reference is a const type. For example: std::cout << std::boolalpha; std::cout << boost::is_const<traits<int>::reference>::value << " "; std::cout << boost::is_const<traits<const int>::reference>::value << std::endl; This outputs: false false Why doesn't it output false true?

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  • What is the rationale to not allow overloading of C++ conversions operator with non-member function

    - by Vicente Botet Escriba
    C++0x has added explicit conversion operators, but they must always be defined as members of the Source class. The same applies to the assignment operator, it must be defined on the Target class. When the Source and Target classes of the needed conversion are independent of each other, neither the Source can define a conversion operator, neither the Target can define a constructor from a Source. Usually we get it by defining a specific function such as Target ConvertToTarget(Source& v); If C++0x allowed to overload conversion operator by non member functions we could for example define the conversion implicitly or explicitly between unrelated types. template < typename To, typename From > operator To(const From& val); For example we could specialize the conversion from chrono::time_point to posix_time::ptime as follows template < class Clock, class Duration> operator boost::posix_time::ptime( const boost::chrono::time_point<Clock, Duration>& from) { using namespace boost; typedef chrono::time_point<Clock, Duration> time_point_t; typedef chrono::nanoseconds duration_t; typedef duration_t::rep rep_t; rep_t d = chrono::duration_cast<duration_t>( from.time_since_epoch()).count(); rep_t sec = d/1000000000; rep_t nsec = d%1000000000; return posix_time::from_time_t(0)+ posix_time::seconds(static_cast<long>(sec))+ posix_time::nanoseconds(nsec); } And use the conversion as any other conversion. For a more complete description of the problem, see here or on my Boost.Conversion library.. So the question is: What is the rationale to non allow overloading of C++ conversions operator with non-member functions?

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  • Visual C++ 2010, rvalue reference bug?

    - by Sergey Shandar
    Is it a bug in Visual C++ 2010 or right behaviour? template<class T> T f(T const &r) { return r; } template<class T> T f(T &&r) { static_assert(false, "no way"); return r; } int main() { int y = 4; f(y); } I thought, the function f(T &&) should never be called but it's called with T = int &. The output: main.cpp(10): error C2338: no way main.cpp(17) : see reference to function template instantiation 'T f<int&>(T)' being compiled with [ T=int & ] Update 1 Do you know any C++x0 compiler as a reference? I've tried comeau online test-drive but could not compile r-value reference. Update 2 Workaround (using SFINAE): #include <boost/utility/enable_if.hpp> #include <boost/type_traits/is_reference.hpp> template<class T> T f(T &r) { return r; } template<class T> typename ::boost::disable_if< ::boost::is_reference<T>, T>::type f(T &&r) { static_assert(false, "no way"); return r; } int main() { int y = 4; f(y); // f(5); // generates "no way" error, as expected. }

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  • mysql 5.0.23 vs 5.5 performance benefits and upgrade issues ?

    - by WarDoGG
    I have been told that mysql 5.5 has a significant performanance boost compared to 5.0 Our server handles alot of data (around 30 million records processed per 5-10 seconds) and requires every drop of performance boost we can give. Will it be beneficial if we upgrade from 5.0.23 to mysql 5.5 ? Also, we have lots of database indexes setup on the tables and i've been told that sometimes the indexes become corrupt after a version upgrade and they have to be rebuilt. Is this true ?

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  • mysql 5.0.23 vs 5.5 performance benefits and upgrade issues?

    - by WarDoGG
    I have been told that mysql 5.5 has a significant performance boost compared to 5.0 Our server handles a lot of data (around 30 million records processed per 5-10 seconds) and requires every drop of performance boost we can give. Will it be beneficial if we upgrade from 5.0.23 to mysql 5.5? Also, we have lots of database indexes setup on the tables and I've been told that sometimes the indexes become corrupt after a version upgrade and they have to be rebuilt. Is this true?

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