local-variables

I was reading my AP cs book and it talked about three types of variables: •Instance variables •Local variables •Parameters Instance variables are visible throughout the class etc... Parameters are only usable within the method and so are local variables . . . Therefore my question is why would they classify Parameters and Local variables as different categories of variables if they contain the same scope. . . Despite the different uses of them. Because they don't necessarily have the same scope. Take this case: // this is garbage code public void doSomething(int foo) { int meh = 0; while (true

If I have a code like this: public class Program { public static void Main() { string bar = ""; int foo = 24; } } I can get the local variables declared in Main using: var flag = BindingFlags.Static | BindingFlags.Public; var fields = typeof(Program).GetMethod("Main", flags).GetMethodBody().LocalVariables; This returns a IList<LocalVariableInfo> and the LocalVariableInfo has only three properties: IsPinned , LocalIndex and LocalType .So there is no Name property exists. What I'm wondering is that you can see the variable names in the generated IL code : .method public hidebysig static void

To understand the stack frame concept, I wrote a little program for my own. First I will show you the code, a little sketch about it and then I will present my question: So, the program: int check_pw(char *password){ int valid = 0; char buffer[10]; strcpy(buffer, password); if(strcmp(buffer, "a") == 0){ valid = 1; } return valid; } int main(int argc, char *argv[]){ if(check_pw(argv[1])){ printf("OK\n"); } else{ printf("Wrong password\n"); } } I give the password as a command-line argument. And if it is equal to 'a', then it is ok. So, I think it is clear. Now the sketch how the stack frame of

This question already has answers here : Is there a 'variable_get' method? If not, how can I create my own? (2 answers) I have a local variable name as a string, and need to get its value. variable = 22 "variable".to_variable? How can I get the value 22 form the string? shivam You can use eval . variable = 22 eval("variable") # => 22 However eval can be nasty . If you dont mind declaring an instance variable, you can do something like this too: @variable = 22 str = "variable" instance_variable_get("@#{str}") # => 22 binding.local_variable_get("variable") # => 22 use eval() method: variable =

Consider the following source: static void Main(string[] args) { bool test; Action lambda = () => { test = true; }; lambda(); if (test) Console.WriteLine("Ok."); } It should compile, right? Well, it doesn't. My question is: according to C# standard, should this code compile or is this a compiler bug? The error message: Use of unassigned local variable 'test' Note: I know , how to fix the error and i partially know , why does it happen. However, the local variable is assigned unconditionally and I guess, that compiler should notice that, but it does not. I wonder, why. Comment for answers: C#

Suppose I have a function in a single threaded program that looks like this void f(some arguments){ char buffer[32]; some operations on buffer; } and f appears inside some loop that gets called often, so I'd like to make it as fast as possible. It looks to me like the buffer needs to get allocated every time f is called, but if I declare it to be static, this wouldn't happen. Is that correct reasoning? Is that a free speed up? And just because of that fact (that it's an easy speed up), does an optimizing compiler already do something like this for me? For implementations that use a stack for