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How to erase the file contents of text file in Python?
...
the reason this works (in both C++ and python) is because by default when you open a file for writing, it truncates the existing contents. So really it's sorta a side effect, and thus I would prefer the explicit call to truncate() for clarity reasons, even though it is unnecessary....
How can I listen to the form submit event in javascript?
...n(){ /*...*/ };
Very straightforward, where $scope is the scope provided by the framework inside your controller. Reference
React
<form onSubmit={this.handleSubmit}>
class YourComponent extends Component {
// stuff
handleSubmit(event) {
// do whatever you need here
...
What size do you use for varchar(MAX) in your parameter declaration?
...har(max) is treated identically to varchar(8000) for values less than 8000 bytes. For larger values the field is treated as a "text" field (aka a "CLOB"). This can affect query plan optimization and the efficiency of retrieving rows with larger values in this column, as the data is stored "out-of-ro...
How to automatically convert strongly typed enum into int?
...on:
Provide type safety, thus eliminating implicit conversion to integer by integral promotion.
Specify underlying types.
Provide strong scoping.
Thus, it is impossible to implicitly convert a strongly typed enum to integers, or even its underlying type - that's the idea. So you have to use stat...
What are good alternatives to SQL (the language)? [closed]
... and ScalaQuery (in Scala)
SqlStatement, ActiveRecord and many others in Ruby,
HaskellDB
...the list goes on for many other languages.
I think that the underlying theme today is that rather than replace SQL with one new query language, we are instead creating language-specific frontends to hide t...
When to make a type non-movable in C++11?
...lue and then set it to zero, but it's still an int with a value, it's just bytes of memory. But an int is still movable in the language terms because a copy is a valid move operation. For non-copyable types however, if you don't want to or can't move the piece of memory and you also can't copy its ...
Are list-comprehensions and functional functions faster than “for loops”?
...pend method on every iteration. However, a list comprehension still does a bytecode-level loop:
>>> dis.dis(<the code object for `[x for x in range(10)]`>)
1 0 BUILD_LIST 0
3 LOAD_FAST 0 (.0)
>> 6 FOR_ITER ...
How do I bind to list of checkbox values with AngularJS?
...pe.selection = ['apple', 'pear'];
// Toggle selection for a given fruit by name
$scope.toggleSelection = function toggleSelection(fruitName) {
var idx = $scope.selection.indexOf(fruitName);
// Is currently selected
if (idx > -1) {
$scope.selection.splice(idx, 1);
}
...
nvarchar(max) vs NText
...limited number of characters. Besides, text and ntext have been deprecated by SQL Server. This means that in a future version, they will no longer be supported.
– Randy Minder
Dec 19 '13 at 22:35
...
How many and which are the uses of “const” in C++?
... can't change
double const PI = 3.1415;
For passing arbitrary objects by reference instead of by value - to prevent possibly expensive or impossible by-value passing
void PrintIt(Object const& obj) {
// ...
}
...