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  • JQuery Load() syntax - Changing data source on mouseenter

    - by Andrew Parisi
    Hey everyone. I've written this simple function that is supposed to load a portion of an XML file on mouseenter. It works fine when I specify the data source explicitly, shown below. I have a number of '.invest-port-thumb' divs, each with a unique link. The following code works fine—but it loads the whole XML file—and I only want a portion: $(document).ready(function() { $('.invest-port-thumb a').mouseenter(function() { $('#slider-name').load(this.href); }); }); This code also works fine—loading only the 'cName' portion that I want it to load...Except that this code refers to one of the files, instead of the value of this.href. $(document).ready(function() { $('.invest-port-thumb a').mouseenter(function() { $('#slider-name').load('port/atd.xml cName'); }); }); I guess what I'm saying, syntax wise—How can I combine this.href and the data matching cName? Thanks for the help!

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  • Magento: The best way to hook into the checkout process

    - by dan.codes
    I am integrating with a third party order management system and I have to make calls to it throughout the checkout process. The problem is, I don't think there are many events available because of how the onepage checkout is all done in javascript/ajax calls. There are a few like after saving the shipping method, and none of the dynamic events seem to fit either. basically I need to know as soon as the user is getting access to the shipping method tab to pass the billing shipping address over, then after the shipping method, to pass that over. Obviously there is an event for that. I know there are ones for when you submit an order so that should be good. I guess I only need to know when the billing/shipping address is saved. I was using controller_action_layout_render_before_checkout_onepage_progress but the progress gets called way to late. It just doesn't seem like there are a lot of hooks through the onepage checkout. if anyone can give me some examples of what they have done that would be great!

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  • What are the best practices for writing maintainable CSS?

    - by Art
    I am just starting to explore this area and wonder what are the best practices when it comes to production of clean, well-structured and maintainable CSSes. There seems to be few different approaches to structuring CSS rules. One of the most commonly encountered ones I saw was throwing everything together in one rule, i.e. margins, borders, typefaces, backgrounds, something like this: .my-class { border-top:1px solid #c9d7f1; font-size:1px; font-weight:normal; height:0; position:absolute; top:24px; width:100%; } Another approach I noticed employed grouping of properties, say text-related properties like font-size, typeface, emphasis etc goes into one rule, backgrounds go into other, borders/margins go into yet another one: .my-class { border-top:1px solid #c9d7f1; } .my-class { font-size:1px; font-weight:normal; } .my-class { height:0; top:24px; width:100%; position:absolute; } I guess I am looking for a silver bullet here which I know I am not going to get, bet nevertheless - what are the best practices in this space?

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  • is it better to query database or grab from file? php & mysql

    - by pfunc
    I am keeping a large amount of words in a database that I want to match up articles to. I was thinking that it would just be better to keep these words in an array and grab that array whenever needed instead of querying the database every time (since the words won't be changing that much). Is there much performance difference in doing this? And if I were to do this, how to I write a script that writes the array to a a new php file. I tried writing the array like so: while( $row = mysql_fetch_assoc($query)) { $newArray[] = $row; } $fp = fopen('noWordsArr.php', 'w'); fwrite($fp, $newArray); fclose($fp); But all I get in the other file is "Array". So i figured I could write this and then write have a chron hit up the file every few days or so in case things have changed. But I guess if there is no performance advantage then it prob won't be necessary and I can just query the database every time I need to access the words.

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  • Develop multiple very similar projects at once

    - by Raveren
    I am developing a semi-complicated site that is available in several countries at once. Much effort has been put in to make the code bases as similar as possible to one another and ultimately only the config file and some representational data will differ between them. Each project has its own SVN repository which maps directly to a live test site. That part is handled by the IDE we use to work. Now I am in need to create a some sort of system to keep all these projects in sync. The best theoretical solution so far is to create a local hook script that would fire on committing and Merge the committed files from the project that is being committed to all other projects Optionally upload them to the live site, replacing previous files The first problem is that I don't know how I would do the merging - I guess it would be like applying a SVN patch or something. The second is if I do not want to upload the changes to the live server, how would I go about synching the live and local code bases (replace older files?). I am posting this question, not going through the potentially huge trouble of solving the aforementioned problems myself is that I believe this is a pretty common situation and someone would already have a solution and others may benefit from the answers in the future. Lastly, I'm on windows7, develop PHP and use tortoiseSVN.

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  • Bruteforcing Blackberry PersistentStore?

    - by Haoest
    Hello, I am experimenting with Blackberry's Persistent Store, but I have gotten nowhere so far, which is good, I guess. So I have written a a short program that attempts iterator through 0 to a specific upper bound to search for persisted objects. Blackberry seems to intentionally slow the loop. Check this out: String result = "result: \n"; int ub = 3000; Date start = Calendar.getInstance().getTime(); for(int i=0; i<ub; i++){ PersistentObject o = PersistentStore.getPersistentObject(i); if (o.getContents() != null){ result += (String) o.getContents() + "\n"; } } result += "end result\n"; result += "from 0 to " + ub + " took " + (Calendar.getInstance().getTime().getTime() - start.getTime()) / 1000 + " seconds"; From 0 to 3000 took 20 seconds. Is this enough to conclude that brute-forcing is not a practical method to breach the Blackberry? In general, how secure is BB Persistent Store?

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  • NotApplicable marker with display pattern

    - by Jeff Barger
    Ok, so I'm pretty new to Cocoa, especially Bindings, but here's what I'm trying to do. I've got a Core Data model consisting of two entities: Category and Item. Category has a to-many relationship to Item called children, and Item has a relationship to Category called parent. Item has two attributes that Category does not have: quantity and desiredQuantity. What I'd like to do is display the tree in an NSOutlineView with two columns. One column is bound to the name of either the Category or the Item. I want to the second column to display something along the lines of 2 of 5 for the Item rows and nothing at all for the Category rows. When I use a display pattern, the Category rows end up showing of I noticed that if I don't use a display pattern for the second column, and instead just bind its Value to either the quantity or the desiredQuantity, the Category rows show nothing; its only if I try to use the display pattern. How can I make it display nothing for the Category rows and still use the display pattern? Or can I? Edit: I guess I didn't explain what the NotApplicable marker has to do with anything - Category does have properties for quantity and desiredQuantity, but they just return NSNotApplicableMarker.

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  • threading in Python taking up too much CPU

    - by KevinShaffer
    I wrote a chat program and have a GUI running using Tkinter, and to go and check when new messages have arrived, I create a new thread so Tkinter keeps doing its thing without locking up while the new thread goes and grabs what I need and updates the Tkinter window. This however becomes a huge CPU hog, and my guess is that it has to do somehow with the fact that the Thread is started and never really released when the function is done. Here's the relevant code (it's ugly and not optimized at the moment, but it gets the job done, and itself does not use too much processing power, as when I run it not threaded, it doesn't take up much CPU but it locks up Tkinter) Note: This is inside of a class, hence the extra tab. def interim(self): threading.Thread(target=self.readLog).start() self.after(5000,self.interim) def readLog(self): print 'reading' try: length = len(str(self.readNumber)) f = open('chatlog'+str(myport),'r') temp = f.readline().replace('\n','') while (temp[:length] != str(self.readNumber)) or temp[0] == '<': temp = f.readline().replace('\n','') while temp: if temp[0] != '<': self.updateChat(temp[length:]) self.readNumber +=1 else: self.updateChat(temp) temp = f.readline().replace('\n','') f.close() Is there a way to better manage the threading so I don't consume 100% of the CPU very quickly?

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  • std::ifstream buffer caching

    - by ledokol
    Hello everybody, In my application I'm trying to merge sorted files (keeping them sorted of course), so I have to iterate through each element in both files to write the minimal to the third one. This works pretty much slow on big files, as far as I don't see any other choice (the iteration has to be done) I'm trying to optimize file loading. I can use some amount of RAM, which I can use for buffering. I mean instead of reading 4 bytes from both files every time I can read once something like 100Mb and work with that buffer after that, until there will be no element in buffer, then I'll refill the buffer again. But I guess ifstream is already doing that, will it give me more performance and is there any reason? If fstream does, maybe I can change size of that buffer? added My current code looks like that (pseudocode) // this is done in loop int i1 = input1.read_integer(); int i2 = input2.read_integer(); if (!input1.eof() && !input2.eof()) { if (i1 < i2) { output.write(i1); input2.seek_back(sizeof(int)); } else input1.seek_back(sizeof(int)); output.write(i2); } } else { if (input1.eof()) output.write(i2); else if (input2.eof()) output.write(i1); } What I don't like here is seek_back - I have to seek back to previous position as there is no way to peek 4 bytes too much reading from file if one of the streams is in EOF it still continues to check that stream instead of putting contents of another stream directly to output, but this is not a big issue, because chunk sizes are almost always equal. Can you suggest improvement for that? Thanks.

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  • problem with a very simple tile based game

    - by newbieguy
    Hello, I am trying to create a pacman-like game. I have an array that looks like this: array: 1111111111111 1000000000001 1111110111111 1000000000001 1111111111111 1 = Wall, 0 = Empty space I use this array to draw tiles that are 16x16 in size. The Game character is 32x32. Initially I represented the character's position in array indexes, [1,1] etc. I would update his position if array[character.new_y][charater.new_x] == 0 Then I translated these array coordinates to pixels, [y*16, x*16] to draw him. He was lining up nicely, wouldn't go into walls, but I noticed that since I was updating him by 16 pixels each, he was moving very fast. I decided to do it in reverse, to store the game character's position in pixels instead, so that he could use less than 16 pixels per move. I thought that a simple if statement such as this: if array[(character.new_pixel_y)/16][(character.new_pixel_x)/16] == 0 would prevent him from going into walls, but unfortunately he eats a bit of the bottom and right side walls. Any ideas how would I properly translate pixel position to the array indexes? I guess this is something simple, but I really can't figure it out :(

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  • Is it possible to customize @synthesized properties?

    - by Dan K.
    I'm probably just being a bit lazy here, but bear with me. Here's my situation. I have a class with two nonatomic, retained properties. Let's say: @property (nonatomic, retain) UITextField *dateField; @property (nonatomic, retain) NSDate *date; I synthesize them as expected in the implementation. What I want to happen is that whenever the setter on date is invoked, it also does something to the dateField (i.e. it sets the text property on the dateField to be a nicely formatted version of the date). I realize I can just manually override the setter for date in my implementation by doing the following: - (void) setDate:(NSDate *)newDate { if (date != newDate) { [date release]; date = [newDate retain]; // my code to touch the dateField goes here } } What would be awesome is if I could let Objective C handle the retain/release cycle, but still be able to "register" (for lack of a better term) a custom handler that would be invoked after the retain/release/set happens. My guess is that isn't possible. My google-fu didn't come up with any answer to this, though, so I thought I'd ask.

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  • zend-framework doctrine, and mvc pattern: what should connect data between models and forms?

    - by Skirmantas
    I am learning Zend Framework and Doctrine. I am wondering what is the best practice to connect forms to models and vice versa. I don't know where I should put my code. I have seen in Zendcast video tutorials where author creates methods like mapFormToRecord and mapRecordToForm in form class. Well I guess it is very handy when form is sophisticated and uses many records. Is it a good practice? I somehow believe that form-class should not need to know about data-records. And sometimes we might have model which is used in many forms. So It would be handy to have few functions in that model which would help to prepare data for forms. For example to give an array of id=name pairs so that it might be used in Zend_Form_Element_Select. However I would like to have a consistency. So I don't want to put this code nor in model nor in form because on different situations I act different. So only controller is what is left to deal it. However this will result in code duplication if one form will be used more than in one controller. Moreover controller gets bloated if form is not from the simple ones. Or maybe there is a consistent pattern in those data conversions between forms and models? I think that there is. At least in my simple cases. So maybe a separate class could be a solution? Where should I put such class and how should I name it? Another question: Zend_Form has validators and filter. Doctrine has validators and filters too. Which do we use and when? What is your way of dealing the connections between forms and models? (Sorry if it was hard for you to read my text. I don't have enough knowledge of English language to express myself freely)

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  • Connecting a django application to a drupal database?

    - by Hans
    I have a 3 - 4000 nodes in a drupal 6 installation on mysql and want to access these data through my django application. I have used manage.py inspectdb to get a skeleton of a model structure. I guess that there are good/historical reasons for drupal's database schemes, but find that there are some hard to understand structure and that there are some challenges in applying django models on the database. Some experiences this far are: node and node revision are intertwined and I solved this by using a OneToOneField (don't need the versions). This meens that the node's body gets accessible through node.vid.body, but it works. Foreign keys need to define the proper db_column to sort out the primary keys. Terms need to use an intermediary table with ManyToManyField.through. Drupal stores both the original and the thumbnailed/resized versions of any image as files in the files table. Does anyone have experiences in accessing drupal data in django? Are there better solution to for example the node <- node revision relationship? Drupal stores time/dates as unix-style timestamps in integerfields. Any recommendations? How about time zones?

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  • CSS/Javascript: multiple columns

    - by Patrick
    hi, I'm looking for a columnizer plugin (making columns of my small divs). It is very important it has the following features: 1) It has to be as light as possible (if it is only css would be great, but I guess it is difficult make it work on IE then...) 2) It has to be cross-browser (I don't need IE6... IE7 and IE8 compatibility is required). 3) The divs has not to be broken. In other terms, the nodes have to be moved to next block but not splitted in 2. The nodes are div elements, they might include other divs, images and text. 4) The column have to have a fixed width and fixed margin. This means that when I resize the browser, and new columns are created (become the window becomes wider), the new columns have to rigidly keep the same width and distance between them. (margin:20px) (width:200px) Would be great to have some css.. but I'm afraid I need some jQuery plugin because I need all 4 features being supported. I found several plugins and css styleshits with very good solutions, but I couldn't find a complete one. Thanks

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  • FluentNHibernate: multiple one-to-many relationships between the same entities.

    - by Venemo
    Hi, I'm working on a bug tracking application. There are tickets, and each ticket has an opener user and an assigned user. So, basically, I have two entities, which have two many-to-one relationships with each other. Their schematic is this: User: public class User { public virtual int Id { get; private set; } ... public virtual IList<Ticket> OpenedTickets { get; set; } public virtual IList<Ticket> AssignedTickets { get; set; } } Ticket: public class Ticket { public virtual int Id { get; protected set; } ... [Required] public virtual User OpenerUser { get; set; } public virtual User AssignedUser { get; set; } } I use FluentNHibernate's auto mapping feature. The problem is, that no matter whether relationship I set, on the side of the User, both collections always contain the same data. I guess Fluent can't tell which end of which relationship belongs to where. I googled around but haven't found anything useful. Could anyone help me, please?

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  • a simple program that counts and sums digits. How can I make it work?

    - by user1710386
    So I've to write a simple program(that loops) where you can enter an int and it spews out the number count and the sum of the numbers. Since I am such a tard when it comes to programming, I just scavanged the code online and tried to piece it together. I guess the sum block screws with n, but I am not really sure. Anyway, I would really appreciate it if somebody could point out mistakes and show me how can I make it work. #include <iostream> using namespace std; int main() { while(1) { int i,p,n,sum=0; //sum block cout<<"enter an int: "; cin>>n; { while(n!=0) { p=n % 10; sum+=p; n=n/10; } cout<<"int digit sum: "<<sum <<endl; } { int count = 0; while(n) { n /= 10; ++count; } cout <<"number of digits: " << count << '\n';} } }

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  • Visual Studio 2008 having problems with namespaces when used as type in Generic coolection

    - by patrick
    I just upgraded last week from Visual Studio 2005 to 2008. I am having an issue with compiler resolving namespaces when I use a class as a type in a Generic collection. Intellisense recognizes the class and the compiler generates no errors when I use the class except when it is a type in a Generic collection declaration either as return type for a Property or as a parameter to a method. This is happening in my only project that is targeting the 3.5 framework, but changing the project containing the class to use the 3.5 framework doesn't fix the problem. Examples Compile fine MyClass myClass = new MyClass(); SortedList <DateTime,MyClass> listOfClasses = new SortedList<DateTime,MyClass> Compile error - Namespace could not be found public SortedList<DateTime,MyClass> ClassList { get; set; } private void DoSomethingToLists(SortedList<DateTime,MyClass> classList) Intellisense has no problem resolving the namespace, only the compiler. Is this a known bug or am I missing something obvious? Will SP1 fix it? I was able to create a new library containing just this class targeting 3.5 and am now able to successfully use this in both 3.5 and 2.0 projects. My guess is that even though I tried to change the target of my original library, since it was still referencing 2.0 projects there was some conflict.

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  • How to configure ldap login with php

    - by Drew G
    I'm attempting to implement a login that works with ldap, My extension=php_ldap.dll is uncommented in both of my php config files, ldap shows up in my phpinfo() I have access to AD and I've been using dsquery to snoop around. So I believe I'm very close to achieving my goal function authenticate($user, $password) { $ldap_host = "na.ad.mycompanyname.com"; $ldap_dn = "CN=USA-USERS,DC=ad,DC=mycompanyname,DC=com"; $ldap_user_group = "Domain Users"; $ldap_manager_group = "Domain Admins"; $ldap_usr_dom = "@na.ad.mycompany.com"; So for now when I enter my login credentials, it fails and I get the appropriate error, my question is, what information do I need to enter and which dsquery commands should I use? Without being spoonfed, could someone point me in the right direction? I've done some extensive research, but nothing I could find really assists with figuring out which CN's and OU's to use. Yes I realize I need to be using the correct CN's and OU's that correspond to my location, but I've been trying the guess and check method to no avail, so I figured I would ask. Any assistance is appreciated. THANKS!!!

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  • Code coverage with phpunit; can't get to one place.

    - by HA17
    In the xdebug code coverage, it shows the line "return false;" (below "!$r") as not covered by my tests. But, the $sql is basically hard-coded. How do I get coverage on that? Do I overwrite "$table" somehow? Or kill the database server for this part of the test? I guess this is probably telling me I'm not writing my model very well, right? Because I can't test it well. How can I write this better? Since this one line is not covered, the whole method is not covered and the reports are off. I'm fairly new to phpunit. Thanks. public function retrieve_all() { $table = $this->tablename(); $sql = "SELECT t.* FROM `{$table}` as t"; $r = dbq ( $sql, 'read' ); if(!$r) { return false; } $ret = array (); while ( $rs = mysql_fetch_array ( $r, MYSQL_ASSOC ) ) { $ret[] = $rs; } return $ret; }

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  • When is it possible to override top-level bindings in (R7RS) scheme?

    - by Marc
    I have read the current draft of the forthcoming R7RS scheme standard (small language), but I don't understand under which conditions it is not an error to redefine top-level bindings. I guess that it is possible to define or set! a binding that has been introduced at the top-level of a program a second time. But what about imported bindings from an external library? Is it possible to override these bindings by the standard? On page 26/27 of the report, it says: The top level of a program may also include import declarations. In a library declaration, it is an error to import the same identifier more than once with different bindings, or to redefine or mutate an imported binding with define, define-syntax or set!. However, a REPL should permit these actions. Does it mean that redefining is only an error when it does happen in libraries for imported bindings? I understand that it prohibits optimisations by compilers if the compiler does not know whether, say + still means the built-in addition or is any other user-specified error. But from this perspective, it does not make sense to restrict forbidding to rebind on the library level, when it would also make sense (at least) for imported bindings in programs. P.S.: As this is all about the environment of a scheme program: am I right in saying that environments are not first class citizens because one cannot get hold of the current environment? (Which, in turn, allows a compiled program to forget about the chosen names of the bindings.)

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  • Call stored proc using xml output from a table

    - by user263097
    Under a tight deadline and I know I can figure this out eventually but I don't have much time to do it on my own. I have a table that has columns for customer id and account number among many other additional columns. There could be many accounts for a single customer (Many rows with the same customer id but different account number). For each customer in the table I need to call a stored procedure and pass data from my table as xml in the following format. Notice that the xml is for all of the customers accounts. <Accounts> <Account> <AccountNumber>12345</AccountNumber> <AccountStatus>Open</AccountStatus> </Account> <Account> <AccountNumber>54321</AccountNumber> <AccountStatus>Closed</AccountStatus> </Account> </Accounts> So I guess I need help with 2 things. First, how to get the data in this xml format. I assuming I'll use some variation of FOR XML. The other thing is how do I group by customer id and then call a sproc for each customer id?

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  • jQuery slideToggle jump on close

    - by spankmaster79
    Hi, I'm trying to slideToggle a in a table with jQuery and it works in FF, OP, CHrome. Only IE (6,7,8) is giving me problems. It slides down perfectly down and up, but after the slide up animation is finished. The hidden pops up in full height and then closes. So I guess it must be somwhere inbetween when it switches from a minimal height to "display:none" that it appears for a short second. The code is built dynamically but I'll try to give an example: <table> <tr> <td> <script type="text/javascript"> function toggleTr_{$dynamicID}() { $('#content_{$dynamicID}').slideToggle('slow'); /* DO SOME OTHER STOFF LIKE COLOR CHANGES CSS CLASS CHANGES */ } </script> </td> </tr> <tr id="list_{$dynamicID}" onclick="toggleTr_{$dynamicID}();" style="cursor:pointer;"> <td> <!-- INFO HEADER --> </td> </tr> <tr> <td> <div id="content_{$dynamicID}" style="display:none;"> <!-- INFO BODY HIDDEN --> </div </td> </tr> Other problems here with slideToggle only descibed problems with padding, margin, or problems with the animation, but that all works. Help is appreciated. Thx, Spanky

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  • What tools do you have at your disposal as a manager to promote a way of thinking

    - by John Leidegren
    This question goes beoynd just programming, but I'd like to get some input on this, if that's okay with the community. Preferably from people that do a lot of coding themselves but also manage other people coding. My problem is this. We have all these ideas that we know is good for the overall strategy of the company and the problem is not figuring out what to do, it's to come about this change. Just telling someone to do things differently isn't enough and it's hard to promote a mind set that is shared within all of the company, (this will take time). If I could jump forward I'd like it if we could create a very nurturing company culture that promotes these ideals cross all areas but I'm not sure what tools to use. And by tools I mean anything I'm legally permitted to do. e.g. we could talk about, we could arrange traning sessions, we could spend more time in meeting (talk about it more), we could spend more time designing, we could spend more time pair-programming, we could add/remove incentive or we could encurage more play. Ultimately if we did all of these things what will be the recurring theme that ties this together. I'd like to be able to answer the question -- why should we do things like this? -- and come up with an answer that explains how important it is to think about our ideals from begining to end. I've puposly avoided to talk about or specifics of the situtation becuase I believe that it narrows things down too much. But I guess, by know you either know how to answer this question or you're as confused as I am ;) I'd love to hear from people who had to bring about a change in order to go from chaos to order, or fix something in the organization which wasn't working. And I'd like to hear it from the perspective of the developer and designer. -- or -- You could simply weigh in on what are the most important qualities in an organization encurage or stimulate rigid fun development cycle from start to finish?

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  • Why does Python's 'for ... in' work differently on a list of values vs. a list of dictionaries?

    - by Code Duck
    I'm wondering about some details of how for ... in works in Python. My understanding is for var in iterable on each iteration creates a variable, var, bound to the current value of iterable. So, if you do for c in cows; c = cows[whatever], but changing c within the loop does not affect the original value. However, it seems to work differently if you're assigning a value to a dictionary key. cows=[0,1,2,3,4,5] for c in cows: c+=2 #cows is now the same - [0,1,2,3,4,5] cows=[{'cow':0},{'cow':1},{'cow':2},{'cow':3},{'cow':4},{'cow':5}] for c in cows: c['cow']+=2 # cows is now [{'cow': 2}, {'cow': 3}, {'cow': 4}, {'cow': 5}, {'cow': 6}, {'cow': 7} #so, it's changed the original, unlike the previous example I see one can use enumerate to make the first example work, too, but that's a different story, I guess. cows=[0,1,2,3,4,5] for i,c in enumerate(cows): cows[i]+=1 # cows is now [1, 2, 3, 4, 5, 6] Why does it affect the original list values in the second example but not the first?

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  • GADTs and Scrap your Boilerplate

    - by finnsson
    I'm writing a XML (de)serializer using Text.XML.Light and Scrap your Boilerplate (at http://github.com/finnsson/Text.XML.Generic) and so far I got working code for "normal" ADTs but I'm stuck at deserializing GADTs. I got the GADT data DataBox where DataBox :: (Show d, Eq d, Data d) => d -> DataBox and I'm trying to get this to compile instance Data DataBox where gfoldl k z (DataBox d) = z DataBox `k` d gunfold k z c = k (z DataBox) -- not OK toConstr (DataBox d) = toConstr d dataTypeOf (DataBox d) = dataTypeOf d but I can't figure out how to implement gunfold for DataBox. The error message is Text/XML/Generic.hs:274:23: Ambiguous type variable `b' in the constraints: `Eq b' arising from a use of `DataBox' at Text/XML/Generic.hs:274:23-29 `Show b' arising from a use of `DataBox' at Text/XML/Generic.hs:274:23-29 `Data b' arising from a use of `k' at Text/XML/Generic.hs:274:18-30 Probable fix: add a type signature that fixes these type variable(s) It's complaining about not being able to figure out the data type of b. I'm also trying to implement dataCast1 and dataCast2 but I think I can live without them (i.e. an incorrect implementation). I guess my questions are: Is it possible to combine GADTs with Scrap your Boilerplate? If so: how do you implement gunfold for a GADT?

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