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How does an underscore in front of a variable in a cocoa objective-c class work?
...to-generated accessor (for the property) knows which ivar to use. Specifically, in your implementation file, your synthesize should look like this:
@synthesize missionName = _missionName;
More generically, this is:
@synthesize propertyName = _ivarName;
...
Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
C++ multiline string literal
...
const char *text2 =
"Here, on the other hand, I've gone crazy \
and really let the literal span several lines, \
without bothering with quoting each line's \
content. This works, but you can't indent.";
Again, note those backslashes at the end of each line, they must be immediately before the...
What is the use of “assert” in Python?
...t True # nothing happens
>>> assert False
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
Assertions can include an optional message, and you can disable them when running the interpreter.
To print a message if the assertion fails:
ass...
PHP array_filter with arguments
...
As an alternative to @Charles's solution using closures, you can actually find an example in the comments on the documentation page. The idea is that you create an object with the desired state ($num) and the callback method (taking $i as an argument):
class LowerThanFilter {
private ...
How do I get the opposite (negation) of a Boolean in Python?
...ful if you want to use a function that requires a predicate-function or a callback.
For example map or filter:
>>> lst = [True, False, True, False]
>>> list(map(operator.not_, lst))
[False, True, False, True]
>>> lst = [True, False, True, False]
>>> list(filter...
Get names of all keys in the collection
I'd like to get the names of all the keys in a MongoDB collection.
21 Answers
21
...
How to dynamically load a Python class
...hing like this won't work:
__import__('foo.bar.baz.qux')
You'd have to call the above function like so:
my_import('foo.bar.baz.qux')
Or in the case of your example:
klass = my_import('my_package.my_module.my_class')
some_object = klass()
EDIT: I was a bit off on this. What you're basicall...
SQL Server - copy stored procedures from one db to another
...you tick the top-level checkbox beside "Stored Procedures" it selects them all together - 1 click.
– Barry Kaye
May 22 '12 at 14:06
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show 4...
PowerShell script to return versions of .NET Framework on a machine?
...t). It also outputs both Client and Full on 4.0 (if you have them both installed):
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse |
Get-ItemProperty -name Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release
Based o...