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How is Racket different from Scheme?
...either. I don't think it can be called 'Scheme' because it's not backwards compatible with any Scheme standard.
Most implementations offer extensions, but are otherwise backwards compatible, of course, the compiler that comes with Racket can also run in R5RS or R6RS mode. Valid R5/6RS Scheme that r...
How to get all subsets of a set? (powerset)
...3,) (1,2) (1,3) (2,3) (1,2,3)"
s = list(iterable)
return chain.from_iterable(combinations(s, r) for r in range(len(s)+1))
Output:
>>> list(powerset("abcd"))
[(), ('a',), ('b',), ('c',), ('d',), ('a', 'b'), ('a', 'c'), ('a', 'd'), ('b', 'c'), ('b', 'd'), ('c', 'd'), ('a', 'b', 'c'...
How to create NS_OPTIONS-style bitmask enumerations in Swift?
...le's documentation about interacting with C APIs, they describe the way NS_ENUM -marked C-style enumerations are imported as Swift enumerations. This makes sense, and since enumerations in Swift are readily provided as the enum value type it's easy to see how to create our own.
...
What is a NullReferenceException, and how do I fix it?
...ic class Form1
{
private Customer customer;
private void Form1_Load(object sender, EventArgs e)
{
Customer customer = new Customer();
customer.Name = "John";
}
private void Button_Click(object sender, EventArgs e)
{
MessageBox.Show(customer....
Merge and interleave two arrays in Ruby
...ult to a variable.
See the set union documentation for the Array class at http://www.ruby-doc.org/core/classes/Array.html#M000275.
This answer assumes that you don't want duplicate array elements. If you want to allow duplicate elements in your final array, a += b should do the trick. Again, if yo...
How to convert Java String into byte[]?
...(Charset.forName("UTF-8"));
byte[] b = string.getBytes(StandardCharsets.UTF_8); // Java 7+ only
However the problem you appear to be wrestling with is that this doesn't display very well. Calling toString() will just give you the default Object.toString() which is the class name + memory address...
What is NSLayoutConstraint “UIView-Encapsulated-Layout-Height” and how should I go about forcing it
...
Try to lower the priority of your _collapsedtextHeightConstraint to 999. That way the system supplied UIView-Encapsulated-Layout-Height constraint always takes precedence.
It is based on what you return in -tableView:heightForRowAtIndexPath:. Make sure to r...
What does static_assert do, and what would you use it for?
Could you give an example where static_assert(...) ('C++11') would solve the problem in hand elegantly?
8 Answers
...
jQuery $(document).ready and UpdatePanels?
...
An UpdatePanel completely replaces the contents of the update panel on an update. This means that those events you subscribed to are no longer subscribed because there are new elements in that update panel.
What I've done to work around th...
How do I get the row count of a pandas DataFrame?
...g",
setup=lambda n: pd.DataFrame(np.arange(n * 3).reshape(n, 3)),
n_range=[2**k for k in range(25)],
kernels=[
lambda data: data.shape[0],
lambda data: data[0].count(),
lambda data: len(data.index),
],
labels=["data.shape[0]", "data[0].count()", "len(data....