scope

问题 First of all, sorry about the title, I just wan't sure how to word this question. So I'm making a task manager using AngularJS. I have a form for the user to fill with the details when he's creating a new task. I use ng-model to save these values to my $scope . Here's how I save them: $scope.add = function(tasks) { { $scope.tasks.push({ 'id': tasks.id, 'title': tasks.title, 'start_day': tasks.start_day, 'start_time':tasks.start_time, 'start_date':tasks.start_day + " " + tasks.start_time, 'end

问题 This is a follow-up question after this (please read my question to the end) : how to avoid name conflicts coming from #define in C? (or C++) Suppose I define ROW and COL using #define. I then define ARRSIZE using ROW and COL. I declare a static array like float myarray[ARRSIZE]; . When I modify ROW and COL, the static array size changes accordingly. But in my special case, the names ROW and COL name-conflicts with a member name of a struct type I'm using in the same file. Someone told me to

问题 This is a follow-up question after this (please read my question to the end) : how to avoid name conflicts coming from #define in C? (or C++) Suppose I define ROW and COL using #define. I then define ARRSIZE using ROW and COL. I declare a static array like float myarray[ARRSIZE]; . When I modify ROW and COL, the static array size changes accordingly. But in my special case, the names ROW and COL name-conflicts with a member name of a struct type I'm using in the same file. Someone told me to

问题 I want to attach functions from a custom environment to the global environment, while masking possible internal functions. Specifically, say that f() uses an internal function g() , then: f() should not be visible in .GlobalEnv with ls(all=TRUE) . f() should be usable from .GlobalEnv . f() internal function g() should not be visible and not usable from .GlobalEnv . First let us create environments and functions as follows: assign('ep', value=new.env(parent=.BaseNamespaceEnv), envir=

问题 I have a ViewModel containing the following observable: self.obFoo = ko.observable({ foo: ko.observable(""), bar: ko.observable("") }); Now I want to add a new computed observable to obFoo that depends on both foo and bar, something like this: self.obFoo = ko.observable({ foo: ko.observable(""), bar: ko.observable(""), foobar: ko.computed(function(){ return foo() + bar(); }) }); The problem is that foo and bar are not defined within the scope of foobar. I tried adding 'this' or even 'self

问题 I would like to perform a query like SELECT * FROM ( SELECT * FROM products ORDER BY price ASC ) AS s GROUP BY item; which return the cheapest of all products for each item. Using this subquery is good because it can run in O(N logN) time. So I can find this with find_by_sql, but it would be nice to be able to chain it with other scopes for Product. Anyone know how to either write this as a scope or chain scoped and find_by_sql? 回答1: You should be able to do something like Product.from("

问题 Given a structure such as below class A { int test; void f() { int test; } } I just had a curious case in which the code in f(), when referring to test, compiled under VS2010, correctly referred to the function local variable, however, when compiled under gcc, incorrectly referred to the member variable. Took me quite a while to track down. Anyway, question is, is there an option in gcc or VS to enable compiler warnings every time a member variable is re-declared in a local function scope?

问题 If I do something like // global scope function stuff() { // local scope var a = new SomeHugeMemoryHog(); } // a doesn't exist down here, but what happened to the memory from the "stuff" scope? Will I create a memory leak if I don't set a = null at the end of the stuff scope? Or should I not worry about it? I'm asking this question with emphasis on creating DOM objects (such as a canvas ) inside the scope of functions (which I don't use later at any time). I'm only using the canvas to grab

问题 A colleague of mine came across an article on codeproject over the weekend which describes the use of the auto_handle method. Given that the article was written in 2006, is that still the right way to handle deterministic disposal for things like file handles? We've tended to explicitly flush and close file handles and then delete the pointers and null them to be certain the GC has no excuse not to collect them (yes, we know we're super-paranoid). Using something like auto_handle looks like

问题 A colleague of mine came across an article on codeproject over the weekend which describes the use of the auto_handle method. Given that the article was written in 2006, is that still the right way to handle deterministic disposal for things like file handles? We've tended to explicitly flush and close file handles and then delete the pointers and null them to be certain the GC has no excuse not to collect them (yes, we know we're super-paranoid). Using something like auto_handle looks like