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  • VB6 Parser/Lexer/Scripter

    - by rlb.usa
    I've got a game in VB6 and it works great and all, but I have been toying with the idea of creating a scripting engine. Ii'm thinking I'd like VB6 to read in flat text script files for me and then lex/parse/execute them. I have good programming experience, and I've built a simple C compiler, as well as a LOGO emulator before. My question is: Are there any tools that I can use, like Lexx/Yakk/Bison to help me? How should I approach this problem in regards to lexing, parsing, and feeding the commands back to VB6 so I can handle them? Is this idea a BAD IDEA in the sense that there are too many obstacles in the way (For example, building minesweeper in assembly, though not impossible, is very difficult, and a bad idea.)?

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  • Segmentation fault in C recursive Combination (nCr)

    - by AruniRC
    PLease help me out here. The program is supposed to recursively find out the combination of two numbers. nCr = n!/ (r!(n-r)! ). I'm getting this error message when i compile it on GCC. Here's what the terminal shows: Enter two numbers: 8 4 Segmentation fault (Program exited with code:139) The code is given here: #include<stdio.h> float nCr(float, float, float); int main() { float a, b, c; printf("Enter two numbers: \n"); scanf("%f%f", &a, &b); c = nCr(a, b, a-b); printf("\n%.3f", c); return 0; } float nCr(float n, float r, float p) { if(n<1) return (1/(p*r))*(nCr(1, r-1, p-1)); if(r<1) return (n/(p*1))*(nCr(n-1, 1, p-1)); if(p<1) return (n/r)*(nCr(n-1, r-1, 1)); return ( n/(p*r) )*nCr(n-1, r-1, p-1); }

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  • Robust DateTime parser library for .NET

    - by Frank Krueger
    Hello, I am writing an RSS and Mail reader app in C# (technically MonoTouch). I have run into the issue of parsing DateTimes. I see a lot of variance in how dates are presented in the wild and have begun writing a function like this: public static DateTime ParseTime(string timeStr) { var formats = new string[] { "ddd, d MMM yyyy H:mm:ss \"GMT+00:00\"", "d MMM yyyy H:mm:ss \"EST\"", "yyyy-MM-dd\"T\"HH:mm:ss\"Z\"", "ddd MMM d HH:mm:ss \"+0000\" yyyy", }; try { return DateTime.Parse(timeStr); } catch (Exception) { } foreach (var f in formats) { try { var t = DateTime.ParseExact(timeStr, f, CultureInfo.InvariantCulture); return t; } catch (Exception) { } } return DateTime.MinValue; } This, well, makes me sick. Three points. (1) It's silly of me to think that I can actually collect a format list that will cover everything out there. (2) It's wrong! Notice that I'm treating an EST date time as UTC (since .NET seems oblivious to time zones). (3) I don't like using exceptions for logic. I am looking for an existing library (source only please) that is known to handle a bunch of these formats. Also, I would like to keep using UTC DateTimes throughout my code so whatever library is suggested should be able to produce DateTimes. Is there anything out there like this?

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  • Recursive wildcards in Rake?

    - by Roger Lipscombe
    Follow up to this question about GNU make: I've got a directory, flac, containing .FLAC files. I've got a corresponding directory, mp3 containing MP3 files. If a FLAC file is newer than the corresponding MP3 file (or the corresponding MP3 file doesn't exist), then I want to run a bunch of commands to convert the FLAC file to an MP3 file, and copy the tags across. The kicker: I need to search the flac directory recursively, and create corresponding subdirectories in the mp3 directory. The directories and files can have spaces in the names, and are named in UTF-8. It turns out that this won't work in make, because of the spaces in the directories and filenames, so I'm wondering how to do it in rake instead...

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  • Recursive COUNT Query (MS SQL)

    - by Cosmo
    Hello Guys! I've two MS SQL tables: Category, Question. Each Question is assigned to exactly one Category. One Category may have many subcategories. Category Id : bigint (PK) Name : nvarchar(255) AcceptQuestions : bit IdParent : bigint (FK) Question Id : bigint (PK) Title : nvarchar(255) ... IdCategory : bigint (FK) How do I recursively count all Questions for a given Category (including questions in subcategories). I've tried it already based on several tutorials but still can't figure it out :(

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  • Recursive powerof-function, see if you can solve it

    - by Jonas B
    First of all, this is not schoolwork - just my curiousity as I for some reason can't get my head around it and solve it. I come up with these stupid things all the time and it annoys the hell out of me when I cant solve them. Code example is in C# but solution doesn't have to be in any particular programming-language. long powerofnum(short num, long powerof) { return powerofnum2(num, powerof, powerof); } long powerofnum2(short num, long powerof, long holder) { if (num == 1) return powerof; else { return powerof = powerofnum2(num - 1, holder * powerof, holder); } } As you can see I have two methods. I call for powerofnum(value, powerofvalue) which then calls the next method with the powerofvalue also in a third parameter as a placeholder so it remembers the original powerof value through the recursion. What I want to accomplish is to do this with only one method. I know I could just declare a variable in the first method with the powerof value to remember it and then iterate from 0 to value of num. But as this is a theoretical question I want it done recursively. I could also in the first method just take a third parameter called whatever to store the value just like I do in the second method that is called by the first, but that looks really stupid. Why should you have to write what seems like the same parameter twice? Rules explained in short: no iteration scope-specific variables only only one method Anyhow, I'd appreciate a clean solution. Good luck :)

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  • Adding some delay in an recursive loop and breaking out of it on mouseover

    - by Moak
    I have created a loop function loopThem(){ $$('#main-nav a').each(function(i, n) { i.up("#main-nav").down("li.active").removeClassName("active"); i.up("li").addClassName("active"); var target = i.readAttribute("href"); i.up(".home-top").down("li.visible").removeClassName("visible"); i.up(".home-top").down(target).addClassName("visible"); }); loopThem(); } This function is called when the dom is loaded document.observe("dom:loaded", function() { loopThem(); }); It does what I want as far as rotating through a set of banners, however it does so at light speed How Can I A add a delay between the changing? B stop the loop from continuing once I mouse over?

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  • Generic JSON parser in .NET / WPF?

    - by niklassaers
    I've read lots of tutorials on how to deserialize a JSON object to an object of a particular using DataContractJsonSerializer. However, I'd like to deserialize my object to a Dictionary consisting of either Strings, Arrays or Dictionaries, such as System.Json does with SilverLight when I say JsonObject.Parse(myJSONstring). Is there an equivalent to System.Json that I can use in my WPF project? (just a short background: I'm fetching JSON objects that have way to much info, and I just want to use a little bit to fill out a String array) Cheers Nik

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  • VB.net XML Parser loop

    - by StealthRT
    Hey all i am new to XML parsing on VB.net. This is the code i am using to parse an XML file i have: Dim output As StringBuilder = New StringBuilder() Dim xmlString As String = _ "<ip_list>" & _ "<ip>" & _ "<ip>192.168.1.1</ip>" & _ "<ping>9 ms</ping>" & _ "<hostname>N/A</hostname>" & _ "</ip>" & _ "<ip>" & _ "<ip>192.168.1.6</ip>" & _ "<ping>0 ms</ping>" & _ "<hostname>N/A</hostname>" & _ "</ip>" & _ "</ip_list>" Using reader As XmlReader = XmlReader.Create(New StringReader(xmlString)) Do Until reader.EOF reader.ReadStartElement("ip_list") reader.ReadStartElement("ip") reader.ReadStartElement("ip") reader.MoveToFirstAttribute() Dim theIP As String = reader.Value.ToString reader.ReadToFollowing("ping") Dim thePing As String = reader.ReadElementContentAsString().ToString reader.ReadToFollowing("hostname") Dim theHN As String = reader.ReadElementContentAsString().ToString MsgBox(theIP & " " & thePing & " " & theHN) Loop End Using I put the "do until reader.EOF" myself but it does not seem to work. It keeps giving an error after the first go around. I must be missing something? David

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  • Trouble parsing self closing XML tags using SAX parser

    - by sandesh
    Hi, I am having trouble parsing self closing XML tags using SAX. I am trying to extract the link tag from the Google Base API.I am having reasonable success in parsing regular tags. Here is a snippet of the xml <entry> <id>http://www.google.com/base/feeds/snippets/15802191394735287303</id> <published>2010-04-05T11:00:00.000Z</published> <updated>2010-04-24T19:00:07.000Z</updated> <category scheme='http://base.google.com/categories/itemtypes' term='Products'/> <title type='text'>En-el1 Li-ion Battery+charger For Nikon Digital Camera</title> <link rel='alternate' type='text/html' href='http://rover.ebay.com/rover/1/711-67261-24966-0/2?ipn=psmain&amp;icep_vectorid=263602&amp;kwid=1&amp;mtid=691&amp;crlp=1_263602&amp;icep_item_id=170468125748&amp;itemid=170468125748'/> . . and so on I can parse the updates and published tags, but not the link and category tag. Here is my startElement and endElement overrides public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException { if (qName.equals("title") && xmlTags.peek().equals("entry")) { insideEntryTitle = true; } xmlTags.push(qName); } public void endElement(String uri, String localName, String qName) throws SAXException { // If a "title" element is closed, we start a new line, to prepare // printing the new title. xmlTags.pop(); if (insideEntryTitle) { insideEntryTitle = false; System.out.println(); } } declaration for xmltags.. private Stack<String> xmlTags = new Stack<String>(); Any help guys? this is my first post here.. I hope I have followed posting rules! thanks a ton guys..

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  • Recursive templates: compilation error under g++

    - by Johannes
    Hi, I am trying to use templates recursively to define (at compile-time) a d-tuple of doubles. The code below compiles fine with Visual Studio 2010, but g++ fails and complains that it "cannot call constructor 'point<1::point' directly". Could anyone please shed some light on what is going on here? Many thanks, Jo #include <iostream> #include <utility> using namespace std; template <const int N> class point { private: pair<double, point<N-1> > coordPointPair; public: point() { coordPointPair.first = 0; coordPointPair.second.point<N-1>::point(); } }; template<> class point<1> { private: double coord; public: point() { coord= 0; } }; int main() { point<5> myPoint; return 0; }

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  • gcc c++ command line error-message parser

    - by Autopulated
    Are there any programs for parsing and displaying in a nice format the c++ error messages generated by gcc. I'm really looking for something like less that I can pipe my errors into that will collapse the template parameter lists by default, maybe with some nice highlighting so that my errors are actually readable. (Yes, it's boost's fault I have such incomprehensible errors, in case you were wondering)

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  • javascript-aware html parser for Python ~

    - by znetor
    <html> <head> <script type="text/javascript"> document.write('<a href="http://www.google.com">f*** js</a>'); document.write("f*** js!"); </script> </head> <body> <script type="text/javascript"> document.write('<a href="http://www.google.com">f*** js</a>'); document.write("f*** js!"); </script> <div><a href="http://www.google.com">f*** js</a></div> </body> </html> I want use xpath to catch all lable object in the html page above... In [1]: import lxml.html as H In [2]: f = open("test.html","r") In [3]: c = f.read() In [4]: doc = H.document_fromstring(c) In [5]: doc.xpath('//a') Out[5]: [<Element a at a01d17c>] In [6]: a = doc.xpath('//a')[0] In [7]: a.getparent() Out[7]: <Element div at a01d41c> I only get one don't generate by js~ but firefox xpath checker can find all lable!? http://i.imgur.com/0hSug.png how to do that??? thx~! <html> <head> </head> <body> <script language="javascript"> function over(){ a.innerHTML="mouse me" } function out(){ a.innerHTML="<a href='http://www.google.com'>google</a>" } </script> <body><li id="a"onmouseover="over()" onmouseout="out()">mouse me</li> </body> </html>

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  • [Android] XML Parser

    - by lemon
    I'm trying to extract n0Y7ezLlIYA8R0K54rEmHaTOraBQVSPDjQaGlQxlGso4jdVN1kRxtcfskEs= using w3c dom <html> <div id='token' style='display:none;'> n0Y7ezLlIYA8R0K54rEmHaTOraBQVSPDjQaGlQxlGso4jdVN1kRxtcfskEs= </div> </html> but I seem to be stuck DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder(); Document doc = builder.parse(con.getInputStream()); NodeList list = doc.getElementsByTagName("div"); Can someone please point me to some basic tutorials that would help me solve my dilemma. Thanks.

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  • Recursive Enumeration in Java

    - by Harm De Weirdt
    Hello everyone. I still have a question about Enumerations. Here's a quick sketch of the situation. I have a class Backpack that has a Hashmap content with as keys a variable of type long, and as value an ArrayList with Items. I have to write an Enumeration that iterates over the content of a Backpack. But here's the catch: in a Backpack, there can also be another Backpack. And the Enumeration should also be able to iterate over the content of a backpack that is in the backpack. (I hope you can follow, I'm not really good at explaining..) Here is the code I have: public Enumeration<Object> getEnumeration() { return new Enumeration<Object>() { private int itemsDone = 0; //I make a new array with all the values of the HashMap, so I can use //them in nextElement() Collection<Long> keysCollection = getContent().keySet(); Long [] keys = keysCollection.toArray(new Long[keysCollection.size()]); public boolean hasMoreElements() { if(itemsDone < getContent().size()) { return true; }else { return false; } } public Object nextElement() { ArrayList<Item> temporaryList= getContent().get(keys[itemsDone]); for(int i = 0; i < temporaryList.size(); i++) { if(temporaryList.get(i) instanceof Backpack) { return temporaryList.get(i).getEnumeration(); }else { return getContent().get(keys[itemsDone++]); } } } }; Will this code work decently? It's just the "return temporaryList.get(i).getEnumeration();" I'm worried about. Will the users still be able to use just the hasMoreElemens() and nextElement() like he would normally do? Any help is appreciated, Harm De Weirdt

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  • Javascript recursive data structure definition

    - by Matt Bierner
    I need to define a data structure recursively in Javascript. Here is a simple example of a circular linked list: // List a very simplified example of what the actual (non list) code does. function List(f, r) { return function(){ return [f, r]; }; } var head = List('a', List('b', List('c', head))); When this is executed, head in List 'c' is resolved to undefined, not List 'a' as I need. List is an example function that returns a function (It is not an Javascript list that I can append to). I tried to wrap the definition of head is a self executing named function, but that blew the stack when head was resolved. What is the Javascript style solution that I am overlooking?

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  • Implementing a recursive menu system a'la Joomla in CodeIgniter

    - by pettersolberg
    Hi I have some sites powered by Joomla, but with my current assignment I wanted to try something new and created with CodeIgniter a really basic CMS (just to suit my client's needs). Everything works fine except menus - multilevel menus like in Joomla, Drupal etc. with items and subitems... My question is: do you know of any tutorials or texts abut implementing such a structure. I've tried the recursion thinggy with while getting children's IDs move downwards from the parent while searching for the currently displayed item's ID. I've tried also the Drupalish way with having a path parameter enclosing ID's all the way from top to bottom '1/23/123/3'. But all in all it was just too chaotic - code something, try it out. If you have some idea on this topic - thanks in advice.

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  • Recursive Iterators

    - by soandos
    I am having some trouble making an iterator that can traverse the following type of data structure. I have a class called Expression, which has one data member, a List<object>. This list can have any number of children, and some of those children might be other Expression objects. I want to traverse this structure, and print out every non-list object (but I do want to print out the elements of the list of course), but before entering a list, I want to return "begin nest" and after I just exited a list, I want to return "end nest". I was able to do this if I ignored the class wherever possible, and just had List<object> objects with List<object> items if I wanted a subExpression, but I would rather do away with this, and instead have an Expressions as the sublists (it would make it easier to do operations on the object. I am aware that I could use extension methods on the List<object> but it would not be appropriate (who wants an Evaluate method on their list that takes no arguments?). The code that I used to generate the origonal iterator (that works) is: public IEnumerator GetEnumerator(){ return theIterator(expr).GetEnumerator(); } private IEnumerable theIterator(object root) { if ((root is List<object>)){ yield return " begin nest "; foreach (var item in (List<object>)root){ foreach (var item2 in theIterator(item)){ yield return item2; } } yield return " end nest "; } else yield return root; } A type swap of List<object> for expression did not work, and lead to a stackOverflow error. How should the iterator be implemented? Update: Here is the swapped code: public IEnumerator GetEnumerator() { return this.GetEnumerator(); } private IEnumerable theIterator(object root) { if ((root is Expression)) { yield return " begin nest "; foreach (var item in (Expression)root) { foreach (var item2 in theIterator(item)) yield return item2; } yield return " end nest "; } else yield return root; }

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