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A field initializer cannot reference the nonstatic field, method, or property
... reminder.TimeSpanText[TimeSpan.FromMinutes(15)];
You cannot use an instance variable to initialize another instance variable. Why? Because the compiler can rearrange these - there is no guarantee that reminder will be initialized before defaultReminder, so the above line might ...
assign multiple variables to the same value in Javascript
...n your code. Don't commit the sin of littering the global namespace with local variables if not absolutely necessary.
Sidenote: As pointed out in the comments (and this is not just in the case of this question), if the copied value in question was not a primitive value but instead an object, you ...
throw new std::exception vs throw std::exception
...
The conventional way to throw and catch exceptions is to throw an exception object and to catch it by reference (usually const reference). The C++ language requires the compiler to generate the appropriate code to construct the exception object and to properl...
Extract elements of list at odd positions
...
Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2...
How to 'bulk update' with Django?
...e to use:
ModelClass.objects.filter(name='bar').update(name="foo")
You can also use F objects to do things like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelCla...
Understanding what 'type' keyword does in Scala
I am new to Scala and I could not really find a lot about the type keyword. I am trying to understand what the following expression may mean:
...
Scala actors: receive vs react
...come interested in functional languages. Recently I've started looking at Scala, which seems like a very nice language.
5 A...
Overlaying histograms with ggplot2 in R
...are visible through each other. So you probably want to use three separate calls to geom_histogram, where each one gets it's own data frame and fill:
ggplot(histogram, aes(f0)) +
geom_histogram(data = lowf0, fill = "red", alpha = 0.2) +
geom_histogram(data = mediumf0, fill = "blue", alpha...
PHP shell_exec() vs exec()
...ream as a string. exec returns the last line of the output by default, but can provide all output as an array specifed as the second parameter.
See
http://php.net/manual/en/function.shell-exec.php
http://php.net/manual/en/function.exec.php
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How Do I Fetch All Old Items on an RSS Feed?
I've been experimenting with writing my own RSS reader. I can handle the "parse XML" bit. The thing I'm getting stuck on is "How do I fetch older posts?"
...