scope

问题 I hope you can help. I am looking for a way to write a function that inserts one item later. Let me show you an example: def general_poly(L): """ L, a list of numbers (n0, n1, n2, ... nk) Returns a function, which when applied to a value x, returns the value n0 * x^k + n1 * x^(k-1) + ... nk * x^0 """ x = 1 res = 0 n = len(L)-1 for e in range(len(L)): res += L[e]*x**n n -= 1 return res I thought I could just give x a value here and once I do general_poly(L)(10) it will be replaced so that x =

问题 I'm new to C. I have a book in front of me that explains C's "file scope", including sample code. But the code only declares and initializes a file scoped variable - it doesn't verify the variable's scope by, say, trying to access it in an illegal way. So! In the spirit of science, I constructed an experiment. File bar.c : static char fileScopedVariable[] = "asdf"; File foo.c : #include <stdio.h> #include "bar.c" main() { printf("%s\n", fileScopedVariable); } According to my book, and to

问题 I needed this myself, so here it is QA-style: By default, Rails Admin shows a model's default_scope. How do I get it to show every model completely unscoped? 回答1: Approach 1 If you only need to list the records you can use the scopes method to control which records are returned. The first array element is the default, so if you add the following to your initialiser: list do scopes [:unscoped] end you will see all records. Approach 2 If you want to do more than list models you can create a

问题 I am reading only firstline from python using : with open(file_path, 'r') as f: my_count = f.readline() print(my_count) I am bit confused over scope of variable my_count. Although prints work fine, would it be better to do something like my_count = 0 outside with statement first (for eg in C in used to do int my_count = 0 ) 回答1: A with statement does not create a scope (like if , for and while do not create a scope either). As a result, Python will analyze the code and see that you made an

问题 I've been looking at some Lua source code, and I often see things like this at the beginning of the file: local setmetatable, getmetatable, etc.. = setmetatable, getmetatable, etc.. Do they only make the functions local to let Lua access them faster when often used? 回答1: Local data are on the stack, and therefore they do access them faster. However, I seriously doubt that the function call time to setmetatable is actually a significant issue for some program. Here are the possible

问题 I am new to iphone development, Now i want to access the string variable in all the view controller, but i know to declare the variables in delegate method, but i cant access it, please help me out. Mainviewcontroller-->Viewcontroller1_-->viewcontroller2-->viewcontroller3-->subwebview. i have created one main view controller and the subview class are Viewcontroller1,viewcontroller2,viewcontroller3. And the subwebview is the subclass of all the three viewcontrollers(Viewcontroller1

问题 This question already has answers here : In what scope are module variables stored in node.js? (4 answers) Closed 5 months ago . In any web browser executing the following script will result in 'wee' being sent to the console. In Node it sends {} . var d = 'wee'; console.log(this.d); I realize that in Node this refers to the exports object in this case. I do know about the global variable, and that isn't what I'm trying to access. Besides, the script above does not set d on the global object

问题 When I open up Chrome (v35) DevTools and inspect an object, the console can show me things nested within functions, including something labeled as the '"function scope". For example, when looking at stackoverflow.com, I can see that there's a global $ object containing another function called Callbacks . Callbacks , as does $ , has a functional scope containing Closure and Global . Question 1: What is the difference between some named object nested directly within a function and some object

问题 I defined a variable in one of my JavaScript files. I want to access the value of that variable among JavaScript files. In one file I am initializing the value of that variable. I cannot access the assigned value in another JS files. Is there anything that I am missing ? 回答1: You should be able to access them if they are in the global scope or can be accessed from the global scope. For example, I have a object literal like this in my HTML in a script element... <script type="text/javascript">

问题 Ok, here's a problem script. var links = [ 'one', 'two', 'three' ]; for( var i = 0; i < links.length; i++ ) { var a = document.createElement( 'div' ); a.innerHTML = links[i]; a.onclick = function() { alert( i ) } document.body.appendChild( a ); } This script generates three divs: one, two and three, using an array. I've set a (Dom0 for simplicity) click handler on each div which alerts the index of its position in the array. - except it doesn't! It always alerts 3, the last index of the array