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How do I create a custom iOS view class and instantiate multiple copies of it (in IB)?
... am currently making an app that will have multiple timers, which are basically all the same.
4 Answers
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How to get the number of days of difference between two dates on mysql?
... the calculation
In your case, you'd use :
mysql> select datediff('2010-04-15', '2010-04-12');
+--------------------------------------+
| datediff('2010-04-15', '2010-04-12') |
+--------------------------------------+
| 3 |
+--------------------------------...
What is a lambda expression in C++11?
... }
} f;
std::for_each(v.begin(), v.end(), f);
}
however this is not allowed, f cannot be passed to a template function in C++03.
The new solution
C++11 introduces lambdas allow you to write an inline, anonymous functor to replace the struct f. For small simple examples this can be cleaner t...
Dynamically replace the contents of a C# method?
What I want to do is change how a C# method executes when it is called, so that I can write something like this:
9 Answers
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Java Date vs Calendar
.... For example, a constant Date in the application (examples: the zero 1970/01/01, or an applicative END_OF_TIME that you set to 2099/12/31 ; those are very useful to replace null values as start time and end time, especially when you persist them in the database, as SQL is so peculiar with nulls).
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Possible to iterate backwards through a foreach?
...g), you cannot do it as efficiently as using a for loop.
Edit: Which generally means, when you are able to use a for loop, it's likely the correct method for this task. Plus, for as much as foreach is implemented in-order, the construct itself is built for expressing loops that are independent of e...
What is the Python equivalent of static variables inside a function?
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there is only one instance of foo - this one function. all invocations access the same variable.
– Claudiu
Nov 10 '08 at 23:49
124
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Add params to given URL in Python
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@florian : At least in python 2.7 you then need to call urlencode as urllib.urlencode(query, doseq=True). Otherwise, parameters that existed in the original url are not preserved correctly (because they are returned as tuples from @parse_qs@
– rluba
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Static way to get 'Context' in Android?
...ontext() {
return MyApplication.context;
}
}
Now everywhere call MyApplication.getAppContext() to get your application context statically.
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How do I modify fields inside the new PostgreSQL JSON datatype?
...a":[null,{"b":[1,2,3]}]}'
For inserting into JSON array (while preserving all of the original values), the jsonb_insert() function can be used (in 9.6+; this function only, in this section):
SELECT jsonb_insert('{"a":[null,{"b":[1]}]}', '{a,1,b,0}', jsonb '2')
-- will yield jsonb '{"a":[null,{"b":[...