Ray's playground

摘要： Template metaprogramming can shift work from runtime to compile-time, thus enabling earlier error detection and higher runtime performance. TMP can be used to generate custom code based on combinations of policy choices, and it can also be used to avoid generating code inappropriate for particular . 阅读全文

摘要： Traits classes make information about types available during compilation. They're implemented using templates and template specializations. In conjunction with overloading, traits classes make it possible to perform compile-time if...else tests on types. 阅读全文

摘要： When writing a class template that offers functions related to the template that support implicit type conversions on all parameters, define those functions as friends inside the class template. 阅读全文

摘要： Use member function templates to generate functions that accept all compatible types. If you declare member templates for generalized copy construction or generalized assignment, you'll still need to declare the normal copy constructor and copy assignment operator, too. 阅读全文

摘要： Templates generate multiple classes and multiple functions, so any template code not dependent on a template parameter causes bloat. Bloat due to non-type template parameters can often be eliminated by replacing template parameters with function parameters or class data members. Bloat due to type p. 阅读全文

摘要： 1#import"Department.h"2#import"Employee.h"34@implementationDepartment5@dynamicdeptName;6@dynamicemployees;7@dynamicmanager;89/*10-(void)addEmployeesObject:(NSManagedObject*)value{11NSSet*changedObjects=[[NSSetalloc]initWithObjects:&valuecount:1];12[selfwillChangeValueForKey:@ 阅读全文

摘要： In derived class templates, refer to names in base class templates via a "this->" prefix, via using declarations, or via an explicit base class qualification. 阅读全文

摘要： Both classes and templates support interfaces and polymorphism. For classes, interfaces are explicit and centered on function signatures. Polymorphism occurs at runtime through virtual functions. For template parameters, interfaces are implicit and based on valid expressions. Polymorphism occurs du. 阅读全文

摘要： Multiple inheritance is more complex than single inheritance. It can lead to new ambiguity issues and to the need for virtual inheritance. Virtual inheritance imposes costs in size, speed, and complexity of initialization and assignment. It's most practical when virtual base classes have no data 阅读全文

摘要： 1importsys23classOutput:4def__init__(self):5self.text=''6defwrite(self,string):7self.text+=string8defwritelines(self,lines):9forlineinlines:10self.write(line)1112classInput:13def__init__(self,input=''):14self.text=input15defread(self,size=None):16ifsize==None:17res,self.text=self.tex 阅读全文