Search Results

Search found 4991 results on 200 pages for 'generator templates'.

Page 47/200 | < Previous Page | 43 44 45 46 47 48 49 50 51 52 53 54  | Next Page >

• c++ class member functions selected by traits

  - by Jive Dadson

  I am reluctant to say I can't figure this out, but I can't figure this out. I've googled and searched stackoverflow, and come up empty. The abstract, and possibly overly vague form of the question is, how can I use the traits-pattern to instantiate non-virtual member functions? The question came up while modernizing a set of multivariate function optimizers that I wrote more than 10 years ago. The optimizers all operate by selecting a straight-line path through the parameter space away from the current best point (the "update"), then finding a better point on that line (the "line search"), then testing for the "done" condition, and if not done, iterating. There are different methods for doing the update, the line-search, and conceivably for the done test, and other things. Mix and match. Different update formulae require different state-variable data. For example, the LMQN update requires a vector, and the BFGS update requires a matrix. If evaluating gradients is cheap, the line-search should do so. If not, it should use function evaluations only. Some methods require more accurate line-searches than others. Those are just some examples. The original version instatiates several of the combinations by means of virtual functions. Some traits are selected by setting mode bits. Yuck. It would be trivial to define the traits with #define's and the member functions with #ifdef's and macros. But that's so twenty years ago. It bugs me that I cannot figure out a whiz-bang modern way. If there were only one trait that varied, I could use the curiously recurring template pattern. But I see no way to extend that to arbitrary combinations of traits. I tried doing it using boost::enable_if, etc.. The specialized state info was easy. I managed to get the functions done, but only by resorting to non-friend external functions that have the this-pointer as a parameter. I never even figured out how to make the functions friends, much less member functions. Perhaps tag-dispatch is the key. I haven't gotten very deeply into that. Surely it's possible, right? If so, what is best practice?

  Read the article

• Get the signed/unsigned variant of an integer template parameter without explicit traits

  - by Blair Holloway

  I am looking to define a template class whose template parameter will always be an integer type. The class will contain two members, one of type T, and the other as the unsigned variant of type T -- i.e. if T == int, then T_Unsigned == unsigned int. My first instinct was to do this: template <typename T> class Range { typedef unsigned T T_Unsigned; // does not compile public: Range(T min, T_Unsigned range); private: T m_min; T_Unsigned m_range; }; But it doesn't work. I then thought about using partial template specialization, like so: template <typename T> struct UnsignedType {}; // deliberately empty template <> struct UnsignedType<int> { typedef unsigned int Type; }; template <typename T> class Range { typedef UnsignedType<T>::Type T_Unsigned; /* ... */ }; This works, so long as you partially specialize UnsignedType for every integer type. It's a little bit of additional copy-paste work (slash judicious use of macros), but serviceable. However, I'm now curious - is there another way of determining the signed-ness of an integer type, and/or using the unsigned variant of a type, without having to manually define a Traits class per-type? Or is this the only way to do it?

  Read the article

• How to check if a variable exists in a FreeMarker template?

  - by Don

  Hi, I have a Freemarker template which contains a bunch of placeholders for which values are supplied when the template is processed. I want to conditionally include part of the template if the userName variable is supplied, something like: [#if_exists userName] Hi ${userName}, How are you? [/#if_exists] However, the FreeMarker manual seems to indicate that if_exists is deprecated, but I can't find another way to achieve this. Of course, I could simple providing an additional boolean variable isUserName and use that like this: [#if isUserName] Hi ${userName}, How are you? [/#if] But if there's a way of checking whether userName exists then I can avoid adding this extra variable. Cheers, Don

  Read the article

• Why is this default template parameter not allowed?

  - by Matt Joiner

  I have the following class: template <typename Type = void> class AlignedMemory { public: AlignedMemory(size_t alignment, size_t size) : memptr_(0) { int iret(posix_memalign((void **)&memptr_, alignment, size)); if (iret) throw system_error("posix_memalign"); } virtual ~AlignedMemory() { free(memptr_); } operator Type *() const { return memptr_; } Type *operator->() const { return memptr_; } //operator Type &() { return *memptr_; } //Type &operator[](size_t index) const; private: Type *memptr_; }; And attempt to instantiate an automatic variable like this: AlignedMemory blah(512, 512); This gives the following error: src/cpfs/entry.cpp:438: error: missing template arguments before ‘buf’ What am I doing wrong? Is void not an allowed default parameter?

  Read the article

• Can I suppress newlines after each template tag with Django's template engine?

  - by ento

  In Rails ERB, you can suppress newlines by adding a trailing hyphen to tags: <ul> <% for @item in @items -%> <li><%= @item %></li> <% end -%> </ul> becomes: <ul> <li>apple</li> <li>banana</li> <li>cacao</li> </ul> Is there a way to do this in Django? (Disclosure: I'm generating a csv file with Django) Edit: Clarified that the newlines I'm hunting down are the ones left behind after the template tags.

  Read the article

• Partial template specialization: matching on properties of specialized template parameter

  - by Kenzo

  template <typename X, typename Y> class A {}; enum Property {P1,P2}; template <Property P> class B {}; class C {}; Is there any way to define a partial specialization of A such that A<C, B<P1> > would be A's normal template, but A<C, B<P2> > would be the specialization? Replacing the Y template parameter by a template template parameter would be nice, but is there a way to partially specialize it based on P then? template <typename X, template <Property P> typename Y> class A {}; // template <typename X> class A<X,template<> Y<P2> > {}; <-- not valid Is there a way by adding traits to a specialization template<> B<P2> and then using SFINAE in A?

  Read the article

• How do I apply a "template" or "skeleton" of code in C# here?

  - by Scott Stafford

  In my business layer, I need many, many methods that follow the pattern: public BusinessClass PropertyName { get { if (this.m_LocallyCachedValue == null) { if (this.Record == null) { this.m_LocallyCachedValue = new BusinessClass( this.Database, this.PropertyId); } else { this.m_LocallyCachedValue = new BusinessClass( this.Database, this.Record.ForeignKeyName); } } return this.m_LocallyCachedValue; } } I am still learning C#, and I'm trying to figure out the best way to write this pattern once and add methods to each business layer class that follow this pattern with the proper types and variable names substituted. BusinessClass is a typename that must be substituted, and PropertyName, PropertyId, ForeignKeyName, and m_LocallyCachedValue are all variables that should be substituted for. Are attributes usable here? Do I need reflection? How do I write the skeleton I provided in one place and then just write a line or two containing the substitution parameters and get the pattern to propagate itself? EDIT: Modified my misleading title -- I am hoping to find a solution that doesn't involve code generation or copy/paste techniques, and rather to be able to write the skeleton of the code once in a base class in some form and have it be "instantiated" into lots of subclasses as the accessor for various properties. EDIT: Here is my solution, as suggested but left unimplemented by the chosen answerer. // I'll write many of these... public BusinessClass PropertyName { get { return GetSingleRelation(ref this.m_LocallyCachedValue, this.PropertyId, "ForeignKeyName"); } } // That all call this. public TBusinessClass GetSingleRelation<TBusinessClass>( ref TBusinessClass cachedField, int fieldId, string contextFieldName) { if (cachedField == null) { if (this.Record == null) { ConstructorInfo ci = typeof(TBusinessClass).GetConstructor( new Type[] { this.Database.GetType(), typeof(int) }); cachedField = (TBusinessClass)ci.Invoke( new object[] { this.Database, fieldId }); } else { var obj = this.Record.GetType().GetProperty(objName).GetValue( this.Record, null); ConstructorInfo ci = typeof(TBusinessClass).GetConstructor( new Type[] { this.Database.GetType(), obj.GetType()}); cachedField = (TBusinessClass)ci.Invoke( new object[] { this.Database, obj }); } } return cachedField; }

  Read the article

• Template operator linker error

  - by Dani

  I have a linker error I've reduced to a simple example. The build output is: debug/main.o: In function main': C:\Users\Dani\Documents\Projects\Test1/main.cpp:5: undefined reference tolog& log::operator<< (char const (&) [6])' collect2: ld returned 1 exit status It looks like the linker ignores the definition in log.cpp. I also cant put the definition in log.h because I include the file alot of times and it complains about redefinitions. main.cpp: #include "log.h" int main() { log() << "hello"; return 0; } log.h: #ifndef LOG_H #define LOG_H class log { public: log(); template<typename T> log &operator <<(T &t); }; #endif // LOG_H log.cpp: #include "log.h" #include <iostream> log::log() { } template<typename T> log &log::operator <<(T &t) { std::cout << t << std::endl; return *this; }

  Read the article

• Comparison of web template engines

  - by Mark

  Post a snippet of code from your favorite templating engine, with the name of the engine and a link to its homepage; show off its basic syntax and maybe some neat features about it that makes it unique. Hopefully this will give people an idea of what's out there and make it easier for them to decide on an engine.

  Read the article

• Form resubmission issue-Django html

  - by Hulk

  There is a form ,which is submitted and then the page is redirected to another page.But if the user hits the refresh button again on the new page .the following message is displayed To display this page, Firefox must send information that will repeat any action (such as a search or order confirmation) that was performed earlier. And on press "OK" A duplicate entry is created how do i prevent this or how do i handle this I am using a django,application Thanks..

  Read the article

• perl dancer: passing database info to template

  - by Bubnoff

  Following Dancer tutorial here: http://search.cpan.org/dist/Dancer/lib/Dancer/Tutorial.pod I'm using my own sqlite3 database with this schema CREATE TABLE if not exists location (location_code TEXT PRIMARY KEY, name TEXT, stations INTEGER); CREATE TABLE if not exists session (id INTEGER PRIMARY KEY, date TEXT, sessions INTEGER, location_code TEXT, FOREIGN KEY(location_code) REFERENCES location(location_code)); My dancer code ( helloWorld.pm ) for the database: package helloWorld; use Dancer; use DBI; use File::Spec; use File::Slurp; use Template; our $VERSION = '0.1'; set 'template' => 'template_toolkit'; set 'logger' => 'console'; my $base_dir = qq(/home/automation/scripts/Area51/perl/dancer); # database crap sub connect_db { my $db = qw(/home/automation/scripts/Area51/perl/dancer/sessions.sqlite); my $dbh = DBI->connect("dbi:SQLite:dbname=$db", "", "", { RaiseError => 1, AutoCommit => 1 }); return $dbh; } sub init_db { my $db = connect_db(); my $file = qq($base_dir/schema.sql); my $schema = read_file($file); $db->do($schema) or die $db->errstr; } get '/' => sub { my $branch_code = qq(BPT); my $dbh = connect_db(); my $sql = q(SELECT * FROM session); my $sth = $dbh->prepare($sql) or die $dbh->errstr; $sth->execute or die $dbh->errstr; my $key_field = q(id); template 'show_entries.tt', { 'branch' => $branch_code, 'data' => $sth->fetchall_hashref($key_field), }; }; init_db(); true; Tried the example template on the site, doesn't work. <% FOREACH id IN data.keys.nsort %> <li>Date is: <% data.$id.sessions %> </li> <% END %> Produces page but with no data. How do I troubleshoot this as no clues come up in the console/cli? Thanks Bubnoff

  Read the article

• if we put template class member function defination in .cpp(not in headerfile) with explicit instant

  - by user323422

  For example //temp.h class ABC { pubilc: void temp(T &a); }; //temp.cpp( ) void ABc<T>::temp(T &a){} //defination ( it should be in header file?????????) template class ABC<int>; //main.cpp int main() { int i=10; ABC<int> a; a.temp(i); return 0; }

  Read the article

• Template error with django-photologue: 'Permission Denied'

  - by Ellie P.

  I'm in the process of re-setting up my Django development environment after reinstalling my OS. We use django-photologue with our project, which I installed using easy_install. However, I'm getting a template error on every template that has a photologue photo: TemplateSyntaxError at /newsroom/news/ Caught an exception while rendering: (13, 'Permission denied') One example of the line where the error is located: <img src="{{ photo.get_list_url }}"> I'm totally stumped--I've used photologue for this project on many different platforms and have never had this problem. Google yields nothing. I'm currently using Jolicloud (based on Ubuntu Jaunty). I'm working with a pre-existing database, so all of the photo sizes and everything have already been set up.

  Read the article

• Can I have a page in my Ruby on Rails app that doesn't use my application.html.erb template?

  - by ben

  I'm using application.html.erb in the views/layouts folder of my Ruby on Rails web app as a template. But there's one page in which I don't want the template to be used. Is this possible?

  Read the article

• Which template technology should I use with CherryPy?

  - by Ben Noland

  I'm in the process of building a web application using cherrypy. What template technology do you recommend I use?

  Read the article

• Help with django filters

  - by Cato Johnston

  In a django template, I want to get an value from the first object in a list's field. I have the following code {{ list.object|first.field }} But it results in an error. Is there a way to achieve this without writing a loop or doing it in the view?

  Read the article

• Sticky footer with CSS Layout Template Module?

  - by boris callens

  I'm currently looking into the JQuery library for CSS Layout Template module Is it possible to define the height of a placeholder with *? Meaning it will push content down if it has to, or fill up any remaining space if the complete content is less then the view port. This would be really nice to make the whole sticky footer thing much easier and robust.

  Read the article

• Choosing the right template engine

  - by asrijaal

  Hi there, since today - I always used simple JSP Tags and JSTL which works but now I'm looking for a little bit more features and maybe more usability. With googling I've found Freemaker, Velocity and Tiles which seem to be very famous. Does someone of you has some further experiences with some of these and can give me a short brief about it. Or are there other frameworks which are worth to look into?

  Read the article

• Drupal6: How to programmatically style a block?

  - by Fronker

  In Drupal6, I basically have a block (a hierarchical menu structure) that turns out like this in HTML: <div class="block block-menu_block" id="block-menu_block-1"> <div class="content"> <div class="menu-block-1 menu-name-menu-navigation parent-mlid-0 menu-level-1"> <ul class="menu"> <li class="leaf first menu-mlid-248 active active-trail"><a class="active-trail active" title="" href="/">Start</a></li> <li class="expanded menu-mlid-249 active"><a class="active" title="" href="/">Aktuell</a> <ul class="menu"> <li class="leaf first menu-mlid-259"> <a title="News und Presse" href="/news-und-presse">News and Press</a> </li>... What I would like to get is actually a lot simpler: <div id="topmenu"> <ul class="one"> <li>some main entry <ul> <li> some sub entry ... or maybe: <div id="topmenu"> <h2>some main entry</h2> <h3><a href="#">some sub entry</a></h3> <h3><a href="#">another sub entry</a></h3> <h2>another main entry</h2> So, keeping the structure, but being able to use simpler, even completely different tags, if and when needed. I think I understand from the drupal docs, that I am (maybe) looking at <div class="block block-menu_block" id="block-menu_block-1" ==> module := menu_block delta := 1 (?) regrettably, none of the suggested * block-[module]-[delta].tpl.php * block-[module].tpl.php * block-[region].tpl.php placed next to page.tpl.php has any impact (yes, I did clear the cache).

  Read the article

• Can I suppress newlines with Django's template engine?

  - by ento

  In Rails ERB, you can suppress newlines by adding a trailing hyphen to tags: <ul> <% for @item in @items -%> <li><%= @item %></li> <% end -%> </ul> becomes: <ul> <li>apple</li> <li>banana</li> <li>cacao</li> </ul> Is there a way to do this in Django? (Disclosure: I'm generating a csv file with Django)

  Read the article

• Display value of a django form field in a template?

  - by Eran Kampf

  I have a form with an email property. When using {{ form.email }} in case of some validation error, django still renders the previous value in the input tag's value attribute: <input type="text" id="id_email" maxlength="75" class="required" value="[email protected]" name="email"> I want to render the input tag myself (to add some javascript code and an error class in case of an error). For example this is my template instead of {{ form.email }}: <input type="text" autocomplete="on" id="id_email" name="email" class="email {% if form.email.errors %}error{% endif %}"> However this does not display the errorneous value ("[email protected]" in this example) to the user. How do I get the field's value in the template?

  Read the article

• C++ adding friend to a template class in order to typecast

  - by user1835359

  I'm currently reading "Effective C++" and there is a chapter that contains code similiar to this: template <typename T> class Num { public: Num(int n) { ... } }; template <typename T> Num<T> operator*(const Num<T>& lhs, const Num<T>& rhs) { ... } Num<int> n = 5 * Num<int>(10); The book says that this won't work (and indeed it doesn't) because you can't expect the compiler to use implicit typecasting to specialize a template. As a soluting it is suggested to use the "friend" syntax to define the function inside the class. //It works template <typename T> class Num { public: Num(int n) { ... } friend Num operator*(const Num& lhs, const Num& rhs) { ... } }; Num<int> n = 5 * Num<int>(10); And the book suggests to use this friend-declaration thing whenever I need implicit conversion to a template class type. And it all seems to make sense. But why can't I get the same example working with a common function, not an operator? template <typename T> class Num { public: Num(int n) { ... } friend void doFoo(const Num& lhs) { ... } }; doFoo(5); This time the compiler complaints that he can't find any 'doFoo' at all. And if i declare the doFoo outside the class, i get the reasonable mismatched types error. Seems like the "friend ..." part is just being ignored. So is there a problem with my understanding? What is the difference between a function and an operator in this case?

  Read the article

• Template metaprogram converting type to unique number

  - by daramarak

  I just started playing with metaprogramming and I am working on different tasks just to explore the domain. One of these was to generate a unique integer and map it to type, like below: int myInt = TypeInt<AClass>::value; I want to know if this is at all possible, and in that case how. Because although I have learned much about exploring this subject I still have failed to come up with an answer. (P.S. A yes/no answer is much more gratifying than a c++ solution that doesn't use metaprogramming, as this is the domain that I am exploring)

  Read the article

• Jquery Template textbox not showing datepicker

  - by pirzada

  I am using Datepicker on one of the the textbox in Jquery template but its not popping up. Outside of the template working fine. Below is what I want to do. jQuery().ready(function () { //$("#HireDate").datepicker(); $("#HireDate").datepicker({dateFormat:'dd-mm-yy', showAnim:'fadeIn'}) }); <script id="UserDetailTemplate" type="text/x-jquery-tmpl"> <table style="width:100%;"> <tbody> <tr> <td style="width:25%;font-weight:bold;">HireDate:</td> <td><input type="text" id="HireDate" value="${ HireDate }" /></td> </tr> </table> </td> </tr> </tbody> </table> </script>

  Read the article

• Django how to handle # in variable name.

  - by Jack

  I've got a dictionary in python which is assigned as a template variable. One of the keys is named "#text" but when i try to access it using {{ artist.image.3."#text"}} I get an error which is File "/home/jack/Desktop/test/appengine/lib/django/django/template/__init__.py", line 558, in __init__ raise TemplateSyntaxError, "Could not parse the remainder: %s" % token[upto:] TemplateSyntaxError: Could not parse the remainder: "#text" So how can I use this in the template? I've tried putting quotes around it but to no avail. I'd like to not modify the dictionary if possible, but if its easy enough to do then I guess its okay. Thanks

  Read the article

< Previous Page | 43 44 45 46 47 48 49 50 51 52 53 54  | Next Page >