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Should I compile with /MD or /MT?
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By dynamically linking with /MD,
you are exposed to system updates (for good or ill),
your executable can be smaller (since it doesn't have the library embedded in it), and
I believe that at very least the code segment of a DLL is...
How can I avoid running ActiveRecord callbacks?
I have some models that have after_save callbacks. Usually that's fine, but in some situations, like when creating development data, I want to save the models without having the callbacks run. Is there a simple way to do that? Something akin to...
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Some built-in to pad a list in python
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a += [''] * (N - len(a))
or if you don't want to change a in place
new_a = a + [''] * (N - len(a))
you can always create a subclass of list and call the method whatever you please
class MyList(list):
def ljust(self, n, fillvalue=''):
return self + [fillvalue] * (n - len(self))
a...
How do I set a ViewModel on a window in XAML using DataContext property?
The question pretty much says it all.
5 Answers
5
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How does the const constructor actually work?
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Const constructor creates a "canonicalized" instance.
That is, all constant expressions begin canonicalized, and later these "canonicalized" symbols are used to recognize equivalence of these constants.
Canonicalization:
A process for converting data that has more than one possible rep...
MySQL: selecting rows where a column is null
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NULL = NULL is not really FALSE - it's NULL again. But it's not TRUE either, so IF(NULL = NULL) won't execute.
– Konerak
Jan 12 '11 at 19:50
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How to add a new method to a php object on the fly?
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You can harness __call for this:
class Foo
{
public function __call($method, $args)
{
if (isset($this->$method)) {
$func = $this->$method;
return call_user_func_array($func, $args);
}
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Why is the gets function so dangerous that it should not be used?
...icial part of the language up to the 1999 ISO C standard, but
it was officially removed by the 2011 standard. Most C implementations still support it, but at least gcc issues a warning for any code that uses it.
share
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Initializing a struct to 0
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The first is easiest(involves less typing), and it is guaranteed to work, all members will be set to 0[Ref 1].
The second is more readable.
The choice depends on user preference or the one which your coding standard mandates.
[Ref 1] Reference C99 Standard 6.7.8.21:
If there are fewe...
How to empty a list?
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This actually removes the contents from the list, but doesn't replace the old label with a new empty list:
del lst[:]
Here's an example:
lst1 = [1, 2, 3]
lst2 = lst1
del lst1[:]
print(lst2)
For the sake of completeness, the slic...