mixins

Is there a way to emulate mixins or traits in java? basically, I need a way to do multiple inheritance so I can add common business logic to several classes Alex B I would encapsulate all of the business logic into a new class BusinessLogic and have each class that needs BusinessLogic make calls to the class. If you need a single rooted heirarchy for your classes that make calls to BusinessLogic , you'll have to create an interface as well ( BusinessLogicInterface ?) In pseudo-code: interface BusinessLogicInterace { void method1(); void method2(); } class BusinessLogic implements

I've got a few fields that I want to add to most every model in my project. For example, these fields are "tracking fields" such as a created date, an update date, and an "active" flag. I'm attempting to create a Mixin that I could add to each model class that would allow me to add these extra fields via multiple inheritance. However, when an object instance is created, it appears that my model fields that were added via the Mixin show up as methods of the object rather than database fields. In [18]: Blog.objects.all()[0].created Out[18]: <django.db.models.fields.DateTimeField object at

Here is the standard CSS I am trying to produce but want to use a SASS Mixin to do the work. STANDARD CSS @-webkit-keyframes crank-up { 100% { -webkit-transform: rotate(360deg);} } @-moz-keyframes crank-up { 100% { -moz-transform: rotate(360deg);} } @-o-keyframes crank-up { 100% { -o-transform: rotate(360deg);} } keyframes crank-up { 100% { transform: rotate(360deg);} } I'm using the same mixin as in the following post SASS keyframes not compiling as wanted which is shown below. MIXIN @mixin keyframes($name) { @-webkit-keyframes #{$name} { @content; } @-moz-keyframes #{$name} { @content; } @

I was trying to figure out how mixins are defined in Maven 3, but couldn't find anything other than buzz. It is propagated as one of the big new features here and here . I am currently feeling the pain of the hierarchical structure and would like to give it a spin. Does anyone have a pointer to documentation or the source defining the syntax even? Pascal Thivent In a comment to this answer , Brett Porter wrote: Maven 3.0 doesn't offer mixins yet, however. – Brett Porter Feb 16 at 8:18 And AFAIK, mixins still aren't there. ngreen Jesse Glick pointed to Maven issue 5102 , so I just wanted to

I have a problem with using variable defaults in Sass across scopes. My test example is: @mixin foo { $val: 'red' !default; .bar { color: $val; } } @include foo; .class1 { $val: 'green'; @include foo; .class11 { @include foo; } } $val: 'black'; .class2 { @include foo; } .class3 { $val: 'blue'; @include foo; } .class4 { @include foo; } It is compiles to: .bar { color: "red"; } .class1 .bar { color: "red"; } .class1 .class11 .bar { color: "red"; } .class2 .bar { color: "black"; } .class3 .bar { color: "blue"; } .class4 .bar { color: "blue"; } As you can see, variable $val is defined as 'red'

I've seen various questions regarding if mixins can be created in C# and they are often directed to the re-mix project on codeplex. However, I don't know if I like the "complete interface" concept. Ideally, I would extend a class like so: [Taggable] public class MyClass { .... } By simply adding the Taggable interface, I can create objects of type MyClass via some kind of object factory. The returned instance would have all the members defined in MyClass as well as all members provided by adding the tagging attribute (like a collection of tags). It seems like this would be easily doable using