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• Unlimited SMS API/Gateway (Sending and Receiving)

  - by Naif

  I am creating a chat application which requires that users be able to send and receive sms messages through a web interface. It would be somewhat similar to the text messaging service available in yahoo mail or in aol instant messenger. The situation is this: Given the high quantity of messages that would be sent and received, paying on a per message basis is not economically feasible. How is it that sites such as yahoo, aim, and twitter can send and receive unlimited sms messages? Essentially, I am looking for a way to send and receive unlimited sms from my computer. Below is a list of some approaches I've come up with but have run into problems with as well. If just one of the approaches can be utilized effectively, then I am fine. As a note on the nature of my application: I will only be sending messages to users that explicitly sign up for the service and permit the receiving of messages. They can unsubscribe at any time. This is to prevent spam. I am aware of software such as Kannel which allows one to connect to a providers smsc gateway. However, this adds the risk of not being approved by the provider which would be unacceptable. Is there any way to significantly mitigate this risk? Utilizing a gateway provider eliminates this risk, but adds the issue of per message pricing. I am also aware of email to sms. However, I have done some testing with that and it appears that this method results in many messages being undelivered or delivered VERY late. If it weren't for that, this approach would have been ideal. Is there any way to negotiate with carriers to remove me from their filters (considering the nature of my service as stated before)? I could use a gsm modem, but even with an "unilimited" plan on a sim card, there are still limits (around 100,000 messages or so). Furthermore, from my understanding, gsm modems are capable of only sending out around a dozen messages per minute. I need to be able to send out as much as several hundred messages per second. During the first 2 months, around 10 messages per second would suffice. There are ways to send out ads with messages to cover the per message costs. However, this is a deal-breaker since it has a high chance of tarnishing the quality of service. Furthermore, I know it is possible to do it without such ads since yahoo, aim, and twitter do not send ads with their messages.

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• What is fastest way to convert bool to byte?

  - by Amir Rezaei

  What is fastest way to convert bool to byte? I want this mapping: False=0, True=1 Note: I don't want to use any if statement. Update: I don't want to use conditional statement. I don't want the CPU to halt or guess next statement. I want to optimize this code: private static string ByteArrayToHex(byte[] barray) { char[] c = new char[barray.Length * 2]; byte k; for (int i = 0; i < barray.Length; ++i) { k = ((byte)(barray[i] >> 4)); c[i * 2] = (char)(k > 9 ? k + 0x37 : k + 0x30); k = ((byte)(barray[i] & 0xF)); c[i * 2 + 1] = (char)(k > 9 ? k + 0x37 : k + 0x30); } return new string(c); } Update: The length of the array is very large, it's in terabyte order! Therefore I need to do optimization if possible. I shouldn't need to explain my self. The question is still valid. Update: I'm working on a project and looking at others code. That's why I didn't provide with the function at first place. I didn't want to spend time on explaining for people when they have opinion about the code. I shouldn’y need to provide in my question the background of my work, and a function that is not written by me. I have started to optimize it part by part. If I needed help with the whole function I would asked that in another question. That is why I asked this very simple at the beginning. Unfortunately people couldn’t keep themselves to the question. So please if you want to help answer the question. Update: For dose who want to see the point of this question. This example shows how two if statement are reduced from the code. byte A = k > 9 ; //If it was possible (k>9) == 0 || 1 c[i * 2] = A * (k + 0x30) - (A - 1) * (k + 0x30);

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• IOC/Autofac problem

  - by Krazzy

  I am currently using Autofac, but am open to commentary regarding other IOC containers as well. I would prefer a solution using Autofac if possible. I am also somewhat new to IOC so I may be grossly misunderstanding what I should be using an IOC container for. Basically, the situation is as follows: I have a topmost IOC container for my app. I have a tree of child containers/scopes where I would like the same "service" (IWhatever) to resolve differently depending on which level in the tree it is resolved. Furthermore if a service is not registered at some level in the tree I would like the tree to be transversed upward until a suitable implementation is found. Furthermore, when constructing a given component, it is quite possible that I will need access to the parent container/scope. In many cases the component that I'm registering will have a dependency on the same or a different service in a parent scope. Is there any way to express this dependency with Autofac? Something like: builder.Register(c=> { var parentComponent = ?.Resolve<ISomeService>(); var childComponent = new ConcreteService(parentComponent, args...); return childComponent; }).As<ISomeService>(); I can't get anything similar to the above pseudocode to work for serveral reasons: A) It seems that all levels in the scope tree share a common set of registrations. I can't seem to find a way to make a given registration confined a certain "scope". B) I can't seem to find a way to get a hold of the parent scope of a given scope. I CAN resolve ILifetimeScope in the container and then case it to a concrete LifetimeScope instance which provides its parent scope, but I'm guessing it is probably note meant to be used this way. Is this safe? C) I'm not sure how to tell Autofac which container owns the resolved object. For many components I would like component to be "owned" by the scope in which it is constructed. Could tagged contexts help me here? Would I have to tag every level of the tree with a unique tag? This would be difficult because the tree depth is determined at runtime. Sorry for the extremely lengthy question. In summary: 1) Is there any way to do what I want to do using Autofac? 2) Is there another container more suited to this kind of dependency structure? 3) Is IOC the wrong tool for this altogether?

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• MooTools event listener disappears after element.innerHTML is changed

  - by acoder

  Hi everyone, I am trying to achieve this task using MooTools. Description: I attached an event listener to "myButton" link. A click on this link initiates an AJAX request and updates "myDiv" content based on the response text. During this request a POST variable is being sent to "button.php", but it's not used at the moment.. (i wish to use it later) OK, as a result, "myDiv" gets exactly the same link with the same ID (myButton) + a random number, so that we could see that each click generates a new number. The problem: After the first click on "myButton", "myDiv" updates correctly, showing a random number. When I click "myButton" for the second time (this time in newly updated div), the div does not refresh anymore. Please note that I need "myButton" to be inside "myDiv", and "myDiv" must be updated (refreshed) after each click without having to refresh the entire page. Can somebody show me how to achieve this task based on this simplified code example? index.html <html> <head> <script type="text/javascript" src="mootools-1.2.4-core-nc.js"></script> <script> window.addEvent('domready', function() { $('myButton').addEvent('click', function(e) { e.stop(); var myRequest = new Request({ method: 'post', url: 'button.php', data: { action : 'test' }, onRequest: function() { $('myDiv').innerHTML = '<img src="images/loading.gif" />'; }, onComplete: function(response) { $('myDiv').innerHTML = response; } }); myRequest.send(); $('myButton').removeEvent('click'); }); }); </script> </head> <body> <div id="myDiv"> <a id="myButton" href="#">Button</a> </div> </body> </html> button.php <a id="myButton" href="#">Button</a> clicked <?php echo rand(1,100); ?>

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• Merge entries in XMLfile (SimpleXML in PHP)

  - by Cudos

  Hello. I have this in my XML file: <product name="iphone"> <variant name="iphone" product_number="12345" price="500" picture="iphone.jpg"> <description><![CDATA[iphone]]></description> <short_description><![CDATA[]]></short_description> <deliverytime><![CDATA[]]></deliverytime> <options> <option group="Color" option="Black" /> </options> </variant> </product> <product name="iphone"> <variant name="iphone" product_number="12345" price="500" picture="iphone.jpg"> <description><![CDATA[iphone]]></description> <short_description><![CDATA[]]></short_description> <deliverytime><![CDATA[]]></deliverytime> <options> <option group="Color" option="White" /> </options> </variant> </product> I want to merge it into this (Note that I merge the options tag): <product name="iphone"> <variant name="iphone" product_number="12345" price="500" picture="iphone.jpg"> <description><![CDATA[iphone]]></description> <short_description><![CDATA[]]></short_description> <deliverytime><![CDATA[]]></deliverytime> <options> <option group="Color" option="Black" /> <option group="Color" option="White" /> </options> </variant> </product> Preferably I want to do it all in the memory since I will process it further afterwards.

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• def constrainedMatchPair(firstMatch,secondMatch,length):

  - by smart

  matches of a key string in a target string, where one of the elements of the key string is replaced by a different element. For example, if we want to match ATGC against ATGACATGCACAAGTATGCAT, we know there is an exact match starting at 5 and a second one starting at 15. However, there is another match starting at 0, in which the element A is substituted for C in the key, that is we match ATGC against the target. Similarly, the key ATTA matches this target starting at 0, if we allow a substitution of G for the second T in the key string. consider the following steps. First, break the key string into two parts (where one of the parts could be an empty string). Let's call them key1 and key2. For each part, use your function from Problem 2 to find the starting points of possible matches, that is, invoke starts1 = subStringMatchExact(target,key1) and starts2 = subStringMatchExact(target,key2) The result of these two invocations should be two tuples, each indicating the starting points of matches of the two parts (key1 and key2) of the key string in the target. For example, if we consider the key ATGC, we could consider matching A and GC against a target, like ATGACATGCA (in which case we would get as locations of matches for A the tuple (0, 3, 5, 9) and as locations of matches for GC the tuple (7,). Of course, we would want to search over all possible choices of substrings with a missing element: the empty string and TGC; A and GC; AT and C; and ATG and the empty string. Note that we can use your solution for Problem 2 to find these values. Once we have the locations of starting points for matches of the two substrings, we need to decide which combinations of a match from the first substring and a match of the second substring are correct. There is an easy test for this. Suppose that the index for the starting point of the match of the first substring is n (which would be an element of starts1), and that the length of the first substring is m. Then if k is an element of starts2, denoting the index of the starting point of a match of the second substring, there is a valid match with one substitution starting at n, if n+m+1 = k, since this means that the second substring match starts one element beyond the end of the first substring. finally the question is Write a function, called constrainedMatchPair which takes three arguments: a tuple representing starting points for the first substring, a tuple representing starting points for the second substring, and the length of the first substring. The function should return a tuple of all members (call it n) of the first tuple for which there is an element in the second tuple (call it k) such that n+m+1 = k, where m is the length of the first substring.

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• Newbie - what do I need to do with httpd.conf to make CakePHP work correctly?

  - by EmmyS

  (Not sure if this belongs here or on webmasters; please move if necessary.) I'm a total newbie to Cake and not much better with apache; I've done a lot of PHP but always with a server that's already been set up by someone else. So I'm going through the basic blog tutorial, and it says: A Note On mod_rewrite Occasionally a new user will run in to mod_rewrite issues, so I'll mention them marginally here. If the Cake welcome page looks a little funny (no images or css styles), it probably means mod_rewrite isn't functioning on your system. Here are some tips to help get you up and running: Make sure that an .htaccess override is allowed: in your httpd.conf, you should have a section that defines a section for each Directory on your server. Make sure the AllowOverride is set to All for the correct Directory. Make sure you are editing the system httpd.conf rather than a user- or site-specific httpd.conf. For some reason or another, you might have obtained a copy of CakePHP without the needed .htaccess files. This sometimes happens because some operating systems treat files that start with '.' as hidden, and don't copy them. Make sure your copy of CakePHP is from the downloads section of the site or our SVN repository. Make sure you are loading up mod_rewrite correctly! You should see something like LoadModule rewrite_module libexec/httpd/mod_rewrite.so and AddModule mod_rewrite.c in your httpd.conf." I'm using XAMPP on linux. I've found my httpd.conf file in opt/lampp/ etc, but am not sure what I need to do with it. I've searched for "rewrite", and there's only one line: LoadModule rewrite_module modules/mod_rewrite.so There's nothing about AddModule mod_rewrite.c. Do I just create a Directory section for the directory I've installed Cake in and set AlllowOverride to All? (I created a separate subdirectory of my wwwroot and installed in there, since I also have installs of Joomla and CodeIgniter.) Is there anything else I need to do? My download of Cake did come with two htaccess-type files (._.htaccess and .htaccess) - do I need to do anything with them? Thanks for any help you can provide to this non-server-admin. EDIT TO ADD virtual host sample: <VirtualHost *:80> ServerAdmin [email protected] DocumentRoot /www/docs/dummy-host.example.com ServerName dummy-host.example.com ServerAlias www.dummy-host.example.com ErrorLog logs/dummy-host.example.com-error_log CustomLog logs/dummy-host.example.com-access_log common </VirtualHost>

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• How to use command bindings in user controls in wpf?

  - by Sam

  In MainWindow the commandbinding works fine. In UserControl1 it doesnt work. Note the datacontext is set correctly as is evidenced by the content of the button which is the result of a binding. I am not trying to bind the command in the usercontrol to a command in mainwindow or any other such trickery. I am just trying to replicate what I did in MainWindow in UserControl1. // MainWindow xaml <StackPanel> <Button Content="Click Here" Command="{Binding ClickHereCommand}" Height="25" Width="90"></Button> <local:UserControl1></local:UserControl1> </StackPanel> // MainWindow public partial class MainWindow : Window { public static RoutedCommand ClickHereCommand { get; set; } public MainWindow() { InitializeComponent(); this.DataContext = this; ClickHereCommand = new RoutedCommand(); CommandBindings.Add(new CommandBinding(ClickHereCommand, ClickHereExecuted)); } public void ClickHereExecuted(object sender, ExecutedRoutedEventArgs e) { System.Windows.MessageBox.Show("hello"); } } // UserControl1 xaml <UserControl x:Class="CommandBindingTest.UserControl1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300" x:Name="root"> <Grid DataContext="{Binding ElementName=root}" > <Button Content="{Binding ButtonContent}" Command="{Binding ClickHereCommand}" Height="25" Width="90"></Button> </Grid> </UserControl> // UserControl1 public partial class UserControl1 : UserControl, INotifyPropertyChanged { private string _ButtonContent; public string ButtonContent { get { return _ButtonContent; } set { if (_ButtonContent != value) { _ButtonContent = value; OnPropertyChanged("ButtonContent"); } } } public static RoutedCommand ClickHereCommand { get; set; } public UserControl1() { InitializeComponent(); ClickHereCommand = new RoutedCommand(); CommandBindings.Add(new CommandBinding(ClickHereCommand, ClickHereExecuted)); ButtonContent = "Click Here"; } public void ClickHereExecuted(object sender, ExecutedRoutedEventArgs e) { System.Windows.MessageBox.Show("hello from UserControl1"); } #region INotifyPropertyChanged Members public event PropertyChangedEventHandler PropertyChanged; public void OnPropertyChanged(string name) { if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(name)); } } #endregion }

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• Subband decomposition using Daubechies filter

  - by misha

  I have the following two 8-tap filters: h0 ['-0.010597', '0.032883', '0.030841', '-0.187035', '-0.027984', '0.630881', '0.714847', '0.230378'] h1 ['-0.230378', '0.714847', '-0.630881', '-0.027984', '0.187035', '0.030841', '-0.032883', '-0.010597'] Here they are on a graph: I'm using it to obtain the approximation (lower subband of an image). This is a(m,n) in the following diagram: I got the coefficients and diagram from the book Digital Image Processing, 3rd Edition, so I trust that they are correct. The star symbol denotes one dimensional convolution (either over rows or over columns). The down arrow denotes downsampling in one dimension (either over rows, or columns). My problem is that the filter coefficients for h0 and h1 sum to greater than 1 (approximately 1.4 or sqrt(2) to be exact). Naturally, if I convolve any image with the filter, the image will get brighter. Indeed, here's what I get (expected result on right): Can somebody suggest what the problem is here? Why should it work if the convolution filter coefficients sum to greater than 1? I have the source code, but it's quite long so I'm hoping to avoid posting it here. If it's absolutely necessary, I'll put it up later. EDIT What I'm doing is: Decompose into subbands Filter one of the subbands Recompose subbands into original image Note that the point isn't just to have a displayable subband-decomposed image -- I have to be able to perfectly reconstruct the original image from the subbands as well. So if I scale the filtered image in order to compensate for my decomposition filter making the image brighter, this is what I will have to do: Decompose into subbands Apply intensity scaling Filter one of the subbands Apply inverse intensity scaling Recompose subbands into original image Step 2 performs the scaling. This is what @Benjamin is suggesting. The problem is that then step 4 becomes necessary, or the original image will not be properly reconstructed. This longer method will work. However, the textbook explicitly says that no scaling is performed on the approximation subband. Of course, it's possible that the textbook is wrong. However, what's more possible is I'm misunderstanding something about the way this all works -- this is why I'm asking this question.

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• C#/.NET Project - Am I setting things up correctly?

  - by JustLooking

  1st solution located: \Common\Controls\Controls.sln and its project: \Common\Controls\Common.Controls\Common.Controls.csproj Description: This is a library that contains this class: public abstract class OurUserControl : UserControl { // Variables and other getters/setters common to our UserControls } 2nd solution located: \AControl\AControl.sln and its project: \AControl\AControl\AControl.csproj Description: Of the many forms/classes, it will contain this class: using Common.Controls; namespace AControl { public partial class AControl : OurUserControl { // The implementation } } A note about adding references (not sure if this is relevant): When I add references (for projects I create), using the names above: 1. I add Common.Controls.csproj to AControl.sln 2. In AControl.sln I turn off the build of Common.Controls.csproj 3. I add the reference to Common.Controls (by project) to AControl.csproj. This is the (easiest) way I know how to get Debug versions to match Debug References, and Release versions to match Release References. Now, here is where the issue lies (the 3rd solution/project that actually utilizes the UserControl): 3rd solution located: \MainProj\MainProj.sln and its project: \MainProj\MainProj\MainProj.csproj Description: Here's a sample function in one of the classes: private void TestMethod<T>() where T : Common.Controls.OurUserControl, new() { T TheObject = new T(); TheObject.OneOfTheSetters = something; TheObject.AnotherOfTheSetters = something_else; // Do stuff with the object } We might call this function like so: private void AnotherMethod() { TestMethod<AControl.AControl>(); } This builds, runs, and works. No problem. The odd thing is after I close the project/solution and re-open it, I have red squigglies everywhere. I bring up my error list and I see tons of errors (anything that deals with AControl will be noted as an error). I'll see errors such as: The type 'AControl.AControl' cannot be used as type parameter 'T' in the generic type or method 'MainProj.MainClass.TestMethod()'. There is no implicit reference conversion from 'AControl.AControl' to 'Common.Controls.OurUserControl'. or inside the actual method (the properties located in the abstract class): 'AControl.AControl' does not contain a definition for 'OneOfTheSetters' and no extension method 'OneOfTheSetters' accepting a first argument of type 'AControl.AControl' could be found (are you missing a using directive or an assembly reference?) Meanwhile, I can still build and run the project (then the red squigglies go away until I re-open the project, or close/re-open the file). It seems to me that I might be setting up the projects incorrectly. Thoughts?

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• ASP.NET MVC 4/Web API Single Page App for Mobile Devices ... Needs Authentication

  - by lmttag

  We have developed an ASP.NET MVC 4/Web API single page, mobile website (also using jQuery Mobile) that is intended to be accessed only from mobile devices (e.g., iPads, iPhones, Android tables and phones, etc.), not desktop browsers. This mobile website will be hosted internally, like an intranet site. However, since we’re accessing it from mobile devices, we can’t use Windows authentication. We still need to know which user (and their role) is logging in to the mobile website app. We tried simply using ASP.NET’s forms authentication and membership provider, but couldn’t get it working exactly the way we wanted. What we need is for the user to be prompted for a user name and password only on the first time they access the site on their mobile device. After they enter a correct user name and password and have been authenticated once, each subsequent time they access the site they should just go right in. They shouldn’t have to re-enter their credentials (i.e., something needs to be saved locally to each device to identify the user after the first time). This is where we had troubles. Everything worked as expected the first time. That is, the user was prompted to enter a user name and password, and, after doing that, was authenticated and allowed into the site. The problem is every time after the browser was closed on the mobile device, the device and user were not know and the user had to re-enter user name and password. We tried lots of things too. We tried setting persistent cookies in JavaScript. No good. The cookies weren’t there to be read the second time. We tried manually setting persistent cookies from ASP.NET. No good. We, of course, used FormsAuthentication.SetAuthCookie(model.UserName, true); as part of the form authentication framework. No good. We tried using HTML5 local storage. No good. No matter what we tried, if the user was on a mobile device, they would have to log in every single time. (Note: we’ve tried on an iPad and iPhone running both iOS 5.1 and 6.0, with Safari configure to allow cookies, and we’ve tried on Android 2.3.4.) Is there some trick to getting a scenario like this working? Or, do we have to write some sort of custom authentication mechanism? If so, how? And, what? Or, should we use something like claims-based authentication and WIF? Or??? Any help is appreciated. Thanks!

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• Rewriting Live TCP/IP (Layer 4) (i.e. Socket Layer) Streams

  - by user213060

  I have a simple problem which I'm sure someone here has done before... I want to rewrite Layer 4 TCP/IP streams (Not lower layer individual packets or frames.) Ettercap's etterfilter command lets you perform simple live replacements of Layer 4 TCP/IP streams based on fixed strings or regexes. Example ettercap scripting code: if (ip.proto == TCP && tcp.dst == 80) { if (search(DATA.data, "gzip")) { replace("gzip", " "); msg("whited out gzip\n"); } } if (ip.proto == TCP && tcp.dst == 80) { if (search(DATA.data, "deflate")) { replace("deflate", " "); msg("whited out deflate\n"); } } http://ettercap.sourceforge.net/forum/viewtopic.php?t=2833 I would like to rewrite streams based on my own filter program instead of just simple string replacements. Anyone have an idea of how to do this? Is there anything other than Ettercap that can do live replacement like this, maybe as a plugin to a VPN software or something? I would like to have a configuration similar to ettercap's silent bridged sniffing configuration between two Ethernet interfaces. This way I can silently filter traffic coming from either direction with no NATing problems. Note that my filter is an application that acts as a pipe filter, similar to the design of unix command-line filters: >[eth0] <----------> [my filter] <----------> [eth1]< What I am already aware of, but are not suitable: Tun/Tap - Works at the lower packet layer, I need to work with the higher layer streams. Ettercap - I can't find any way to do replacements other than the restricted capabilities in the example above. Hooking into some VPN software? - I just can't figure out which or exactly how. libnetfilter_queue - Works with lower layer packets, not TCP/IP streams. Again, the rewriting should occur at the transport layer (Layer 4) as it does in this example, instead of a lower layer packet-based approach. Exact code will help immensely! Thanks!

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• Best way to return result from business layer to presentation layer when using LINQ-to-SQL

  - by samsur

  I have a business layer that has DTOs that are used in the presentation layer. This application uses entity framework. Here is an example of a class called RoleDTO: public class RoleDTO { public Guid RoleId { get; set; } public string RoleName { get; set; } public string RoleDescription { get; set; } public int? OrganizationId { get; set; } } In the BLL I want to have a method that returns a list of DTO. I would like to know which is the better approach: returning IQueryable or list of DTOs. Although I feel that returning IQueryable is not a good idea because the connection needs to be open. Here are the 2 different methods using the different approaches: First approach public class RoleBLL { private servicedeskEntities sde; public RoleBLL() { sde = new servicedeskEntities(); } public IQueryable<RoleDTO> GetAllRoles() { IQueryable<RoleDTO> role = from r in sde.Roles select new RoleDTO() { RoleId = r.RoleID, RoleName = r.RoleName, RoleDescription = r.RoleDescription, OrganizationId = r.OrganizationId }; return role; } Note: in the above method the DataContext is a private attribute and set in the constructor, so that the connection stays opened. Second approach public static List<RoleDTO> GetAllRoles() { List<RoleDTO> roleDTO = new List<RoleDTO>(); using (servicedeskEntities sde = new servicedeskEntities()) { var roles = from pri in sde.Roles select new { pri.RoleID, pri.RoleName, pri.RoleDescription }; //Add the role entites to the DTO list and return. This is necessary as anonymous types can be returned acrosss methods foreach (var item in roles) { RoleDTO roleItem = new RoleDTO(); roleItem.RoleId = item.RoleID; roleItem.RoleDescription = item.RoleDescription; roleItem.RoleName = item.RoleName; roleDTO.Add(roleItem); } return roleDTO; } } Please let me know, if there is a better approach.

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• How does Sentry aggregate errors?

  - by Hugo Rodger-Brown

  I am using Sentry (in a django project), and I'd like to know how I can get the errors to aggregate properly. I am logging certain user actions as errors, so there is no underlying system exception, and am using the culprit attribute to set a friendly error name. The message is templated, and contains a common message ("User 'x' was unable to perform action because 'y'"), but is never exactly the same (different users, different conditions). Sentry clearly uses some set of attributes under the hood to determine whether to aggregate errors as the same exception, but despite having looked through the code, I can't work out how. Can anyone short-cut my having to dig further into the code and tell me what properties I need to set in order to manage aggregation as I would like? [UPDATE 1: event grouping] This line appears in sentry.models.Group: class Group(MessageBase): """ Aggregated message which summarizes a set of Events. """ ... class Meta: unique_together = (('project', 'logger', 'culprit', 'checksum'),) ... Which makes sense - project, logger and culprit I am setting at the moment - the problem is checksum. I will investigate further, however 'checksum' suggests that binary equivalence, which is never going to work - it must be possible to group instances of the same exception, with differenct attributes? [UPDATE 2: event checksums] The event checksum comes from the sentry.manager.get_checksum_from_event method: def get_checksum_from_event(event): for interface in event.interfaces.itervalues(): result = interface.get_hash() if result: hash = hashlib.md5() for r in result: hash.update(to_string(r)) return hash.hexdigest() return hashlib.md5(to_string(event.message)).hexdigest() Next stop - where do the event interfaces come from? [UPDATE 3: event interfaces] I have worked out that interfaces refer to the standard mechanism for describing data passed into sentry events, and that I am using the standard sentry.interfaces.Message and sentry.interfaces.User interfaces. Both of these will contain different data depending on the exception instance - and so a checksum will never match. Is there any way that I can exclude these from the checksum calculation? (Or at least the User interface value, as that has to be different - the Message interface value I could standardise.) [UPDATE 4: solution] Here are the two get_hash functions for the Message and User interfaces respectively: # sentry.interfaces.Message def get_hash(self): return [self.message] # sentry.interfaces.User def get_hash(self): return [] Looking at these two, only the Message.get_hash interface will return a value that is picked up by the get_checksum_for_event method, and so this is the one that will be returned (hashed etc.) The net effect of this is that the the checksum is evaluated on the message alone - which in theory means that I can standardise the message and keep the user definition unique. I've answered my own question here, but hopefully my investigation is of use to others having the same problem. (As an aside, I've also submitted a pull request against the Sentry documentation as part of this ;-)) (Note to anyone using / extending Sentry with custom interfaces - if you want to avoid your interface being use to group exceptions, return an empty list.)

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• Android database closed exception

  - by Bombastic

  I'm working on a project where I'm downloading and saving data from web to sqlite database. A few minutes ago I receive a strange exception to our server from a user which is saying that the sqlite database is already closed..and I just checked the whole file where the exception happened and I'm not calling dbHelper.close();. Here is the function where the app crashes and LogCat message : public void insertCollectionCountries(JSONObject obj, Context context) { //Insert in collection_countries if(RPCCommunicator.isServiceRunning){ Log.w("","JsonCollection - insertCollectionCountries"); ContentValues valuesCountries = new ContentValues(); try { collectionId = Integer.parseInt(obj.getString("collection_id")); dbHelper.deleteSQL("collection_countries", "collection_id=?", new String[] {Integer.toString(collectionId)}); JSONArray arrayCountries = obj.getJSONArray("country_availability"); for (int i=0; i<arrayCountries.length(); i++) { valuesCountries.put("collection_id", collectionId); String countryCode = arrayCountries.getString(i); valuesCountries.put("country_code", countryCode); dbHelper.executeQuery("collection_countries", valuesCountries); } } catch (JSONException e){ e.printStackTrace(); } } } and the error is on that line : dbHelper.executeQuery("collection_countries", valuesCountries); here is the LogCat message : java.lang.IllegalStateException: database /data/data/com.stampii.stampii/databases/stampii_sys_tpl.sqlite (conn# 0) already closed at android.database.sqlite.SQLiteDatabase.verifyDbIsOpen(SQLiteDatabase.java:2123) at android.database.sqlite.SQLiteDatabase.setTransactionSuccessful(SQLiteDatabase.java:734) at com.stampii.stampii.comm.rpc.SystemDatabaseHelper.execQuery(SystemDatabaseHelper.java:298) at com.stampii.stampii.comm.rpc.SystemDatabaseHelper.executeQuery(SystemDatabaseHelper.java:291) at com.stampii.stampii.jsonAPI.JsonCollection.insertCollectionCounries(JsonCollection.java:548) at com.stampii.stampii.jsonAPI.JsonCollection.executeInsert(JsonCollection.java:181) at com.stampii.stampii.collections.MyService.downloadCollections(MyService.java:122) at com.stampii.stampii.collections.MyService$2.run(MyService.java:74) at java.lang.Thread.run(Thread.java:1020) and function in my dbHelperClass which I'm using to insert data : public boolean executeQuery(String tableName,ContentValues values){ return execQuery(tableName,values); } private boolean execQuery(String tableName,ContentValues values){ sqliteDb = instance.getWritableDatabase(); sqliteDb.beginTransaction(); sqliteDb.insert(tableName, null, values); sqliteDb.setTransactionSuccessful(); sqliteDb.endTransaction(); return true; } Any ideas which can close my sqlite database or what can cause that exception, because I've tested this code on a few emulators with different Android versions, different devices (HTC EVO 3D, Samsung Galaxy Nexus,HTC Desire, LG OPTIMUS PAD, Samsung Galaxy S2, Samsung Galaxy Note) and it's working fine. Thanks in advance!

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• small scale web site - global javascript file style/format/pattern - improving maintainability

  - by yaya3

  I frequently create (and inherit) small to medium websites where I have the following sort of code in a single file (normally named global.js or application.js or projectname.js). If functions get big, I normally put them in a seperate file, and call them at the bottom of the file below in the $(document).ready() section. If I have a few functions that are unique to certain pages, I normally have another switch statement for the body class inside the $(document).ready() section. How could I restructure this code to make it more maintainable? Note: I am less interested in the functions innards, more so the structure, and how different types of functions should be dealt with. I've also posted the code here - http://pastie.org/999932 in case it makes it any easier var ProjectNameEnvironment = {}; function someFunctionUniqueToTheHomepageNotWorthMakingConfigurable () { $('.foo').hide(); $('.bar').click(function(){ $('.foo').show(); }); } function functionThatIsWorthMakingConfigurable(config) { var foo = config.foo || 700; var bar = 200; return foo * bar; } function globallyRequiredJqueryPluginTrigger (tooltip_string) { var tooltipTrigger = $(tooltip_string); tooltipTrigger.tooltip({ showURL: false ... }); } function minorUtilityOneLiner (selector) { $(selector).find('li:even').not('li ul li').addClass('even'); } var Lightbox = {}; Lightbox.setup = function(){ $('li#foo a').attr('href','#alpha'); $('li#bar a').attr('href','#beta'); } Lightbox.init = function (config){ if (typeof $.fn.fancybox =='function') { Lightbox.setup(); var fade_in_speed = config.fade_in_speed || 1000; var frame_height = config.frame_height || 1700; $(config.selector).fancybox({ frameHeight : frame_height, callbackOnShow: function() { var content_to_load = config.content_to_load; ... }, callbackOnClose : function(){ $('body').height($('body').height()); } }); } else { if (ProjectNameEnvironment.debug) { alert('the fancybox plugin has not been loaded'); } } } // ---------- order of execution ----------- $(document).ready(function () { urls = urlConfig(); (function globalFunctions() { $('.tooltip-trigger').each(function(){ globallyRequiredJqueryPluginTrigger(this); }); minorUtilityOneLiner('ul.foo') Lightbox.init({ selector : 'a#a-lightbox-trigger-js', ... }); Lightbox.init({ selector : 'a#another-lightbox-trigger-js', ... }); })(); if ( $('body').attr('id') == 'home-page' ) { (function homeFunctions() { someFunctionUniqueToTheHomepageNotWorthMakingConfigurable (); })(); } });

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• asp:Button is not calling server-side function

  - by Richard Neil Ilagan

  Hi guys, I know that there has been much discussion here about this topic, but none of the threads I got across helped me solve this problem. I'm hoping that mine is somewhat unique, and may actually merit a different solution. I'm instantiating an asp:Button inside a data-bound asp:GridView through template fields. Some of the buttons are supposed to call a server-side function, but for some weird reason, it doesn't. All the buttons do when you click them is fire a postback to the current page, doing nothing, effectively just reloading the page. Below is a fragment of the code: <asp:GridView ID="gv" runat="server" AutoGenerateColumns="false" CssClass="l2 submissions" ShowHeader="false"> <Columns> <asp:TemplateField> <ItemTemplate><asp:Panel ID="swatchpanel" CssClass='<%# Bind("status") %>' runat="server"></asp:Panel></ItemTemplate> <ItemStyle Width="50px" CssClass="sw" /> </asp:TemplateField> <asp:BoundField DataField="description" ReadOnly="true"> </asp:BoundField> <asp:BoundField DataField="owner" ReadOnly="true"> <ItemStyle Font-Italic="true" /> </asp:BoundField> <asp:BoundField DataField="last-modified" ReadOnly="true"> <ItemStyle Width="100px" /> </asp:BoundField> <asp:TemplateField> <ItemTemplate> <asp:Button ID="viewBtn" cssclass='<%# Bind("sid") %>' runat="server" Text="View" OnClick="viewBtnClick" /> </ItemTemplate> </asp:TemplateField> </Columns> </asp:GridView> The viewBtn above should call the viewBtnClick() function on server-side. I do have that function defined, along with a proper signature (object,EventArgs). One thing that may be of note is that this code is actually inside an ASCX, which is loaded in another ASCX, finally loaded into an ASPX. Any help or insight into the matter will be SO appreciated. Thanks! (oh, and please don't mind my trashy HTML/CSS semantics - this is still in a very,very early stage :p)

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• waiting for 2 different events in a single thread

  - by João Portela

  component A (in C++) - is blocked waiting for alarm signals (not relevant) and IO signals (1 udp socket). has one handler for each of these. component B (java) - has to receive the same information the component A udp socket receives. periodicaly gives instructions that should be sent through component A udp socket. How to join both components? it is strongly desirable that: the changes to attach component B to component A are minimal (its not my code and it is not very pleasent to mess with). the time taken by the new operations (usually communicating with component B) interfere very little with the usual processing time of component A - this means that if the operations are going to take a "some" time I would rather use a thread or something to do them. note: since component A receives udp packets more frequently that it has component B instructions to forward, if necessary, it can only forward the instructions (when available) from the IO handler. my initial ideia was to develop a component C (in C++) that would sit inside the component A code (is this called an adapter?) that when instanciated starts the java process and makes the necessary connections (that not so little overhead in the initialization is not a problem). It would have 2 stacks, one for the data to give component B (lets call it Bstack) and for the data to give component A (lets call it Astack). It would sit on its thread (lets call it new-thread) waiting for data to be available in Bstack to send it over udp, and listen on the udp socket to put data on the Astack. This means that the changes to component A are only: when it receives a new UDP packet put it on the Bstack, and if there is something on the Astack sent it over its UDP socket (I decided for this because this socket would only be used in the main thread). One of the problems is that I don't know how to wait for both of these events at the same time using only one thread. so my questions are: Do I really need to use the main thread to send the data over component A socket or can I do it from the new-thread? (I think the answer is no, but I'm not sure about race conditions on sockets) how to I wait for both events? boost::condition_variable or something similar seems the solution in the case of the stack and boost::asio::io_service io_service.run() seems like the thing to use for the socket. Is there any other alternative solution for this problem that I'm not aware of? Thanks for reading this long text but I really wanted you to understand the problem.

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• PHP running as a FastCGI application (php-cgi) - how to issue concurrent requests?

  - by Sbm007

  Some background information: I'm writing my own webserver in Java and a couple of days ago I asked on SO how exactly Apache interfaces with PHP, so I can implement PHP support. I learnt that FastCGI is the best approach (since mod_php is not an option). So I have looked at the FastCGI protocol specification and have managed to write a working FastCGI wrapper for my server. I have tested phpinfo() and it works, in fact all PHP functions seem to work just fine (posting data, sessions, date/time, etc etc). My webserver is able to serve requests concurrently (ie user1 can retrieve file1.html at the same time as user2 requesting some_large_binary_file.zip), it does this by spawning a new Java thread for each user request (terminating when completed or user connection with client is cancelled). However, it cannot deal with 2 (or more) FastCGI requests at the same time. What it does is, it queues them up, so when request 1 is completed immediately thereafter it starts processing request 2. I tested this with 2 PHP pages, one contains sleep(10) and the other phpinfo(). How would I go about dealing with multiple requests as I know it can be done (PHP under IIS runs as FastCGI and it can deal with multiple requests just fine). Some more info: I am coding under windows and my batch file used to execute php-cgi.exe contains: set PHP_FCGI_CHILDREN=8 set PHP_FCGI_MAX_REQUESTS=500 php-cgi.exe -b 9000 But it does not spawn 8 children, the service simply terminates after 500 requests. I have done research and from Wikipedia: Processing of multiple requests simultaneously is achieved either by using a single connection with internal multiplexing (ie. multiple requests over a single connection) and/or by using multiple connections Now clearly the multiple connections isn't working for me, as everytime a client requests something that involves FastCGI it creates a new socket to the FastCGI application, but it does not work concurrently (it queues them up instead). I know that internal multiplexing of FastCGI requests under the same connection is accomplished by issuing each unique FastCGI request with a different request ID. (also see the last 3 paragraphs of 'The Communication Protocol' heading in this article). I have not tested this, but how would I go about implementing that? I take it I need some kind of FastCGI Java thread which contains a Map of some sort and a static function which I can use to add requests to. Then in the Thread's run() function it would have a while loop and for every cycle it would check whether the Map contains new requests, if so it would assign them a request ID and write them to the FastCGI stream. And then wait for input etc etc, As you can see this becomes too complicated. Does anyone know the correct way of doing this? Or any thoughts at all? Thanks very much. Note, if required I can supply the code for my FastCGI wrapper.

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• Implementing Object Oriented: ansi-C approach

  - by No Money

  Hey there, I am an Intermediate programmer in Java and know some of the basics in C++. I recently started to scam over "C language" [please note that i emphasized on C language and want to stick with C as i found it to be a perfect tool, so no need for suggestions focusing on why should i move back to C++ or Java or any other crappy language (e.g: C#)]. Moving on, I code an Object Oriented approach in C but kindda scramble with the pointers part. Please understand that I am just a noob trying to extend my knowledge beyond what i learned in High School. Here is my code..... #include <stdio.h> typedef struct per{ int privateint; char *privateString; struct per (*New) (); void (*deleteperOBJ) (struct t_person *); void (*setperNumber) ((struct*) t_person,int); void (*setperString) ((struct*) t_person,char *); void (*dumpperState) ((struct*) t_person); }t_person; void setperNumber(t_person *const per,int num){ if(per==NULL) return; per->privateint=num; } void setperString(t_person *const per,char *string){ if(per==NULL) return; per->privateString=string; } void dumpperState(t_person *const per){ if(per==NULL) return; printf("value of private int==%d\n", per->privateint); printf("value of private string==%s\n", per->privateString); } void deleteperOBJ(struct t_person *const per){ free((void*)t_person->per); t_person ->per = NULL; } main(){ t_person *const per = (struct*) malloc(sizeof(t_person)); per = t_person -> struct per -> New(); per -> setperNumber (t_person *per, 123); per -> setperString(t_person *per, "No money"); dumpperState(t_person *per); deleteperOBJ(t_person *per); } Just to warn you, this program has several errors and since I am a beginner I couldn't help except to post this thread as a question. I am looking forward for assistance. Thanks in advance.

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• Remote Postgresql - extremely slow

  - by Muffinbubble

  Hi, I have setup PostgreSQL on a VPS I own - the software that accesses the database is a program called PokerTracker. PokerTracker logs all your hands and statistics whilst playing online poker. I wanted this accessible from several different computers so decided to installed it on my VPS and after a few hiccups I managed to get it connecting without errors. However, the performance is dreadful. I have done tons of research on 'remote postgresql slow' etc and am yet to find an answer so am hoping someone is able to help. Things to note: The query I am trying to execute is very small. Whilst connecting locally on the VPS, the query runs instantly. While running it remotely, it takes about 1 minute and 30 seconds to run the query. The VPS is running 100MBPS and then computer I'm connecting to it from is on an 8MB line. The network communication between the two is almost instant, I am able to remotely connect fine with no lag whatsoever and am hosting several websites running MSSQL and all the queries run instantly, whether connected remotely or locally so it seems specific to PostgreSQL. I'm running their newest version of the software and the newest compatible version of PostgreSQL with their software. The database is a new database, containing hardly any data and I've ran vacuum/analyze etc all to no avail, I see no improvements. I don't understand how MSSQL can query almost instantly yet PostgreSQL struggles so much. I am able to telnet to the post 5432 on the VPS IP with no problems, and as I say the query does execute it just takes an extremely long time. What I do notice is on the router when the query is running that hardly any bandwidth is being used - but then again I wouldn't expect it to for a simple query but am not sure if this is the issue. I've tried connecting remotely on 3 different networks now (including different routers) but the problem remains. Connecting remotely via another machine via the LAN is instant. I have also edited the postgre conf file to allow for more memory/buffers etc but I don't think this is the problem - what I am asking it to do is very simple - it shouldn't be intensive at all. Thanks, Ricky

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• How to manipulate file paths intelligently in .Net 3.0?

  - by Hamish Grubijan

  Scenario: I am maintaining a function which helps with an install - copies files from PathPart1/pending_install/PathPart2/fileName to PathPart1/PathPart2/fileName. It seems that String.Replace() and Path.Combine() do not play well together. The code is below. I added this section: // The behavior of Path.Combine is weird. See: // http://stackoverflow.com/questions/53102/why-does-path-combine-not-properly-concatenate-filenames-that-start-with-path-dir while (strDestFile.StartsWith(@"\")) { strDestFile = strDestFile.Substring(1); // Remove any leading backslashes } Debug.Assert(!Path.IsPathRooted(strDestFile), "This will make the Path.Combine(,) fail)."); in order to take care of a bug (code is sensitive to a constant @"pending_install\" vs @"pending_install" which I did not like and changed (long story, but there was a good opportunity for constant reuse). Now the whole function: //You want to uncompress only the files downloaded. Not every file in the dest directory. private void UncompressFiles() { string strSrcDir = _application.Client.TempDir; ArrayList arrFiles = new ArrayList(); GetAllCompressedFiles(ref arrFiles, strSrcDir); IEnumerator enumer = arrFiles.GetEnumerator(); while (enumer.MoveNext()) { string strDestFile = enumer.Current.ToString().Replace(_application.Client.TempDir, String.Empty); // The behavior of Path.Combine is weird. See: // http://stackoverflow.com/questions/53102/why-does-path-combine-not-properly-concatenate-filenames-that-start-with-path-dir while (strDestFile.StartsWith(@"\")) { strDestFile = strDestFile.Substring(1); // Remove any leading backslashes } Debug.Assert(!Path.IsPathRooted(strDestFile), "This will make the Path.Combine(,) fail)."); strDestFile = Path.Combine(_application.Client.BaseDir, strDestFile); strDestFile = strDestFile.Replace(Path.GetExtension(strDestFile), String.Empty); ZSharpLib.ZipExtractor.ExtractZip(enumer.Current.ToString(), strDestFile); FileUtility.DeleteFile(enumer.Current.ToString()); } } Please do not laugh at the use of ArrayList and the way it is being iterated - it was pioneered by a C++ coder during a .Net 1.1 era. I will change it. What I am interested in: what is a better way of replacing PathPart1/pending_install/PathPart2/fileName with PathPart1/PathPart2/fileName within the current code. Note that _application.Client.TempDir is just _application.Client.BaseDir + @"\pending_install". While there are many ways to improve the code, I am mainly concerned with the part which has to do with String.Replace(...) and Path.Combine(,). I do not want to make changes outside of this function. I wish Path.Combine(,) took an optional bool flag, but it does not. So ... given my constraints, how can I rework this so that it starts to sucks less? Thanks!

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• Can someone who understands C code help me understand this code?

  - by Benjamin

  INT GetTree (HWND hWnd, HTREEITEM hItem, HKEY *pRoot, TCHAR *pszKey, INT nMax) { TV_ITEM tvi; TCHAR szName[256]; HTREEITEM hParent; HWND hwndTV = GetDlgItem (hWnd, ID_TREEV); memset (&tvi, 0, sizeof (tvi)); hParent = TreeView_GetParent (hwndTV, hItem); if (hParent) { // Get the parent of the parent of the... GetTree (hWnd, hParent, pRoot, pszKey, nMax); // Get the name of the item. tvi.mask = TVIF_TEXT; tvi.hItem = hItem; tvi.pszText = szName; tvi.cchTextMax = dim(szName); TreeView_GetItem (hwndTV, &tvi); //send the TVM_GETITEM message? lstrcat (pszKey, TEXT ("\\")); lstrcat (pszKey, szName); } else { *pszKey = TEXT ('\0'); szName[0] = TEXT ('\0'); // Get the name of the item. tvi.mask = TVIF_TEXT | TVIF_PARAM; tvi.hItem = hItem; tvi.pszText = szName; tvi.cchTextMax = dim(szName); if (TreeView_GetItem (hwndTV, &tvi)) //*pRoot = (HTREEITEM)tvi.lParam; //original hItem = (HTREEITEM)tvi.lParam; else { INT rc = GetLastError(); } } return 0; } The block of code that begins with the comment "Get the name of the item" does not make sense to me. If you are getting the listview item why does the code set the parameters of the item being retrieved, because if you already had the values there would be no need to retrieve them. Secondly near the comment "original" is the original line of code which will compile with a varning under embedded visual c++, but if you copy the exact same code into visual studio 2008 it will not compile. Since I did not write any of this code and am trying to learn is it possible the original author made a mistake on this line, since the *pRoot should point to and HKEY type yet he is casting to an HTREEITEM type which should never work since the data types don't match? (Side note someone with a better reputation should add a windows ce tag to SO since windows mobile is not the same as windows ce.)

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• Algorithm: Determine shape of two sectors delineated by an arbitrary path, and then fill one.

  - by Arseniy Banayev

  NOTE: This is a challenging problem for anybody who likes logic problems, etc. Consider a rectangular two-dimensional grid of height H and width W. Every space on the grid has a value, either 0 1 or 2. Initially, every space on the grid is a 0, except for the spaces along each of the four edges, which are initially a 2. Then consider an arbitrary path of adjacent (horizontally or vertically) grid spaces. The path begins on a 2 and ends on a different 2. Every space along the path is a 1. The path divides the grid into two "sectors" of 0 spaces. There is an object that rests on an unspecified 0 space. The "sector" that does NOT contain the object must be filled completely with 2. Define an algorithm that determines the spaces that must become 2 from 0, given an array (list) of values (0, 1, or 2) that correspond to the values in the grid, going from top to bottom and then from left to right. In other words, the element at index 0 in the array contains the value of the top-left space in the grid (initially a 2). The element at index 1 contains the value of the space in the grid that is in the left column, second from the top, and so forth. The element at index H contains the value of the space in the grid that is in the top row but second from the left, and so forth. Once the algorithm finishes and the empty "sector" is filled completely with 2s, the SAME algorithm must be sufficient to do the same process again. The second (and on) time, the path is still drawn from a 2 to a different 2, across spaces of 0, but the "grid" is smaller because the 2s that are surrounded by other 2s cannot be touched by the path (since the path is along spaces of 0). I thank whomever is able to figure this out for me, very very much. This does not have to be in a particular programming language; in fact, pseudo-code or just English is sufficient. Thanks again! If you have any questions, just leave a comment and I'll specify what needs to be specified.

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• urgent..haskell mini interpreter

  - by mohamed elshikh

  i'm asked to implement this project and i have problems in part b which is the eval function this is the full describtion of the project You are required to implement an interpreter for mini-Haskell language. An interpreter is dened in Wikipedia as a computer program that executes, i.e. performs, instructions written in a programming language. The interpreter should be able to evaluate functions written in a special notation, which you will dene. A function is dened by: Function name Input Parameters : dened as a list of variables. The body of the function. The body of the function can be any of the following statements: a) Variable: The function may return any of the input variables. b) Arithmetic Expressions: The arithmetic expressions include input variables and addition, sub- traction, multiplication, division and modulus operations on arithmetic expressions. c) Boolean Expressions: The Boolean expressions include the ordering of arithmetic expressions (applying the relationships: <, =<, , = or =) and the anding, oring and negation of Boolean expressions. d) If-then-else statements: where the if keyword is followed by a Boolean expression. The then and else parts may be followed by any of the statements described here. e) Guarded expressions: where each case consists of a boolean expression and any of the statements described here. The expression consists of any number of cases. The rst case whose condition is true, its body should be evaluated. The guarded expression has to terminate with an otherwise case. f) Function calls: the body of the function may have a call to another function. Note that all inputs passed to the function will be of type Int. The output of the function can be of type Int or Bool. To implement the interpreter, you are required to implement the following: a) Dene a datatype for the following expressions: Variables Arithmetic expressions Boolean expressions If-then-else statements Guarded expressions Functions b) Implement the function eval which evaluates a function. It takes 3 inputs: The name of a function to be evaluated represented as a string. A list of inputs to that function. The arguments will always be of datatype Int. A list of functions. Each function is represented as instance of the datatype that you have created for functions. c) Implement the function get_type that returns the type of the function (as a string). The input to this function is the same as in part b. here is what i've done data Variable = v(char) data Arth= va Variable | Add Arth Arth | Sub Arth Arth | Times Arth Arth | Divide Arth Arth data Bol= Great Arth Arth | Small Arth Arth | Geq Arth Arth | Seq Arth Arth | And Bol Bol | Or Bol Bol | Neg Bol data Cond = data Guard = data Fun =cons String [Variable] Body data Body= bodycons(String) |Bol |Cond |Guard |Arth

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