caption adder

else: raise AttributeError,attrname X = empty() print X.age #call__getattr__ class accesscontrol: def __setattr__(self, attr, value): if attr == 'age': # Self.attrname = value loops! self.__dict__[attr] = value else: print attr raise AttributeError, attr + 'not allowed' X = accesscontrol() X.age = 40 #call __setattr__ X.name = 'wang' #raise exception class empty: def __getattr__(self,attrname): if attrname == 'age': return 4

, which expands the addressing capability.Physical Address = Segment Address *16+ offset addressThe address Adder uses the physical address = Segment Address *16+ offset address to synthesize the physical address with the segment address and offset address. For example, 8086CPU wants to access 123c8h's memory unit, at which point the Adder uses 1230H and 00c8h two addresses to form the 123c8h address.We can

parameter and returns an alternative function. The following is a simple example: def add_number(func):def adder(arg):return func(arg)+100return adderdef f(x):return xf=add_number(f)print f(20) Add_number is a modifier function. It accepts a function (f) as a parameter and returns another function (adder) to assign a value to the original function. In this way, the original function implements the addition

Python calls the C language method [Based on the ctypes module], pythonctypes This example describes how to call C language in Python. We will share this with you for your reference. The details are as follows: The ctypes module in Python may be the simplest way for Python to call the C method. The ctypes module provides data types and functions compatible with the C language to load dll files. Therefore, you do not need to modify the source files during the call. This laid the simplicity of thi

(ID); }; = null;}2. Variable namingIf the variables of the intrinsic function and the variable name of the external function are the same, then the intrinsic function cannot point to the variable with the same name as the outer function.Like what:function foo (num) { returnfunction(num) { console.log (num); }} var New foo (9// undefinedIn fact, the above usage, the jargon called function currying, is to transform a function that accepts multiple parameters into a function that takes

data is performed, and the operation can be given to the function object for processing.In addition, in some common operations, there are often different special operations, while the differential operation can be encapsulated with a function.package mainimport "fmt"func adder() func(int) int { sum := 0 f := func(x int) int { sum += x return sum } return f}func main() { sum := adder()

itself.A timestamp lock has an optimistic mode in which each lock operation returns a timestamp as a permission credential, and each unlocking operation needs to provide its corresponding timestamp. If a thread requests a write lock and the lock happens to be held by a read operation, the unlock of the read operation will be invalidated (because the timestamp has been invalidated). This time the application needs to start over, perhaps using pessimistic mode locks (timestamp locks are also impl

Python instance It's always a little confusing to look at the concept, so just look at a few Python examples. Example 1 def make_adder (addend):def adder (augend):return augend + addendReturn adder p = Make_adder (23)Q = Make_adder (44) Print P (100)Print Q (100)Run Result: 123144Analyze: We found that the Make_adder is a function, including a parameter addend, the special place is that this function

, but basically no URL contains so complete, because the HTTP default port number is 80, often omitted, so usually use protocol, address, path three parts is enough to locate a host of some resources, such as the following URL Http://www.balabala.com/index.html Where HTTP is the protocol used, www.balabala.com represents the target server's host IP or hostname,/index.html represents the target host's resource path In addition to the above three parts, there are more occurrences of the query str

above examples are rewritten as follows: class Adder{ private: int _total; public: Adder() : _total(0) {} void operator ( ) ( int i ) { _total += i; } operator int ( ) { return _total; } }; void VectorAdd() { std::vector﹤int﹥ v; v.push_back(1); v.push_back(5); int total = std::for_each(v.begin(), v.end(), Adder()); } Here, the specific for loop is discarded, a