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Creating an abstract class in Objective-C
I'm originally a Java programmer who now works with Objective-C. I'd like to create an abstract class, but that doesn't appear to be possible in Objective-C. Is this possible?
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Difference between “module.exports” and “exports” in the CommonJs Module System
...ns to be set to module.exports.
At the end of your file, node.js will basically 'return' module.exports to the require function. A simplified way to view a JS file in Node could be this:
var module = { exports: {} };
var exports = module.exports;
// your code
return module.exports;
If you set a...
Combining INSERT INTO and WITH/CTE
...ions go at the top.
Wrapping every insert in a CTE has the benefit of visually segregating the query logic from the column mapping.
Spot the mistake:
WITH _INSERT_ AS (
SELECT
[BatchID] = blah
,[APartyNo] = blahblah
,[SourceRowID] = blahblahblah
FROM Table1 AS t1
)
INSERT ...
Instance variables vs. class variables in Python
...r instance. If there would be more than one instance (which won't happen), all instance should have the same configuration. I wonder which of the following options would be better or more "idiomatic" Python.
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How to dynamic new Anonymous Class?
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All you're doing is saying that dynamic properties are not identical to strongly-typed properties. This is trivially true.
– Steven Sudit
Sep 18 '10 at 2:31
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Why do people say there is modulo bias when using a random number generator?
...AND_MAX is 10 and I decide to generate a random number between 0 and 2 by calling rand()%3. However, rand()%3 does not produce the numbers between 0 and 2 with equal probability!
When rand() returns 0, 3, 6, or 9, rand()%3 == 0. Therefore, P(0) = 4/11
When rand() returns 1, 4, 7, or 10, rand()%3 ...
Call a python function from jinja2
I am using jinja2, and I want to call a python function as a helper, using a similar syntax as if I were calling a macro. jinja2 seems intent on preventing me from making a function call, and insists I repeat myself by copying the function into a template as a macro.
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How do I run a single test with Nose in Pylons
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nosetests appname.tests.functional.test_controller should work, where the file is named test_controller.py.
To run a specific test class and method use a path of the form module.path:ClassNameInFile.method_name, that is, with a colon separating the module/file pa...
Create a menu Bar in WPF?
...nel>
<Menu DockPanel.Dock="Top">
<MenuItem Header="_File">
<MenuItem Header="_Open"/>
<MenuItem Header="_Close"/>
<MenuItem Header="_Save"/>
</MenuItem>
</Menu>
<StackPanel></StackPa...
Run a callback only if an attribute has changed in Rails
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Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c6a08383b974ae...