variable-assignment

问题 Please see the following code: public static void main(String[] args) { Test t1 = new Test(); t1.i = 1; Test t0 = t1; Test t2 = new Test(); t2.i = 2; t0 = t2; System.out.println(t1.i); //prints 1, I thought it would print 2 } Is there any way to change t1 object after I got it from somewhere else by simple assignment without accessing t1 directly? (i.e. t1 = t0) 回答1: Here is an illustration of your program and what it does. Each state of the system is shown separated by a dashed line. Note

问题 I have multiple assignment statement in my program as shown below where query.constraints.size() is supposed to return 13 ( constraints is an array and its returning its size) int num,size = query.constraints.size(); When I do this size becomes 13 as expected but num becomes 9790272 for some reason. When I do them separately as below everything is ok and both of them are 13 as expected int size = query.constraints.size(); int num = query.constraints.size(); Why does my multiple assignment

问题 I am working on a project in C#, and for some reason, when I try to assign a value to an enum variable, the assignment does not happen. I would copy my code, but it is really just a simple assignment. It's something like: testVar = MyEnum.TYPE_OF_ENUM; where testVar is of type MyEnum . When I step through this line using the VisualStudio debugger, I can see that the value of testVar does not change. What could possibly make an assignment fail like that? EDIT: Ok I will provide more context.

问题 -This code is written in verilog using Modelsim 10.2d.The errors below indicate there is some problem with {cout,l3} assignment. module alu(a,b,bin,cin,op,cout,res); input [31:0] a,b; input [1:0] op; input bin,cin; reg [31:0] l1,l2,l3; output cout; output [31:0] res; assign l1 = a & b; assign l2 = a | b; initial if(bin == 1'b0) assign {cout,l3} = a + b + cin; else assign {cout,l3} = a - b + cin; mux4to1(l1,l2,l3,op,res); endmodule Error- v(14): LHS in procedural continuous assignment may not

问题 I'm working on a project where there are some global assignments, and I ran into something sort of odd. I was hoping someone could help me with it. I wrote this toy example to demonstrate the problem: x <- 1:3 ; x <- c(1, 2, 5) # this works fine x <- 1:3 ; x[3] <- 5 # this works fine x <<- 1:3 ; x <<- c(1, 2, 5) # this works fine x <<- 1:3 ; x[3] <<- 5 # this does not work # Error in x[3] <<- 5 : object 'x' not found same.thing.but.in.a.function = function() { x <<- 1:3 x[3] <<- 5 } same

问题 This is probably easy but I am confused as hell with environments. I would like to use a call to a function to assign a value to a variable, but I need to be able to use that variable after the call. However, I assume, the variable created by the function only exist within the function environment. In short, I need something akin to a global variable (but I am a beginner with R). The following code : assignvalue = function(varname){ assign(varname,1) } assignvalue("test") test returns Error:

问题 I am working on a project with a library and I must work with unions. Specifically I am working with SDL and the SDL_Event union. I need to make copies of the SDL_Events, and I could find no good information on overloading assignment operators with unions. Provided that I can overload the assignment operator, should I manually sift through the union members and copy the pertinent members or can I simply come some members (this seems dangerous to me), or maybe just use memcpy() (this seems

问题 I'm trying to assign the values of a string to different array indexes but I'm getting an error called "list assignment out of range" uuidVal = "" distVal = "" uuidArray = [] distArray = [] for i in range(len(returnedList)): for beacon in returnedList: uuidVal= uuidVal+beacon[:+2] uuidArray[i]= uuidVal distVal= distVal+beacon[-2:] distArray[i]= distVal uuidVal="" disVal="" I tried using distArray[i].append(distVal) instead of distArray[i]= distVal but it gave an error called "list index out

问题 I would like to create a class that behaves as a python variable but calls some callback function when the "variable" is changed/read. In other words, I'd like to be able to use the class as follows: x=myClass(change_callback, read_callback) defines x as an instance of myclass. The constructor ( INIT ) takes 2 functions as paramater: a function to be called each time x is changed, and a function to be called each time x is "read" The following statement: x=1 would "save" 1 and trigger a call

问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: Java - Order of Operations - Using Two Assignment Operators in a Single Line If we assign a variable a value in a chain like the following, int x=10, y=15; int z=x=y; System.out.println(x+" : "+y+" : "+z); then the value of all three variables x , y and z becomes 15 . I however don't understand the following phenomenon with an array. int array[]={10, 20, 30, 40, 50}; int i = 4; array[i] = i = 0; System.out