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Speed comparison with Project Euler: C vs Python vs Erlang vs Haskell
I have taken Problem #12 from Project Euler as a programming exercise and to compare my (surely not optimal) implementations in C, Python, Erlang and Haskell. In order to get some higher execution times, I search for the first triangle number with more than 1000 divisors instead of 500 as stated...
What is the difference between the 'COPY' and 'ADD' commands in a Dockerfile?
What is the difference between the COPY and ADD commands in a Dockerfile, and when would I use one over the other?
13 A...
Seedable JavaScript random number generator
The JavaScript Math.random() function returns a random value between 0 and 1, automatically seeded based on the current time (similar to Java I believe). However, I don't think there's any way to set you own seed for it.
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What is the difference between `new Object()` and object literal notation?
...done something unusual), other than that your second one creates an object and adds a property to it. But literal notation takes less space in the source code. It's clearly recognizable as to what is happening, so using new Object(), you are really just typing more and (in theory, if not optimized ...
Java: convert List to a String
...; list = Arrays.asList("foo", "bar", "baz");
String joined = String.join(" and ", list); // "foo and bar and baz"
If you have a Collection with another type than String you can use the Stream API with the joining Collector:
List<Person> list = Arrays.asList(
new Person("John", "Smith"),
...
Proper indentation for Python multiline strings
... one
line two
line three"""
Since the newlines and spaces are included in the string itself, you will have to postprocess it. If you don't want to do that and you have a whole lot of text, you might want to store it separately in a text file. If a text file does not work ...
Deep null checking, is there a better way?
...ing a new operation "?." to the language that has the semantics you want. (And it has been added now; see below.) That is, you'd say
cake?.frosting?.berries?.loader
and the compiler would generate all the short-circuiting checks for you.
It didn't make the bar for C# 4. Perhaps for a hypothetic...
how to implement a pop up dialog box in iOS
... say display a custom UI in your UIAlertView, you can subclass UIAlertView and put in custom UI components in the init method. If you want to respond to a button press after a UIAlertView appears, you can set the delegate above and implement the - (void)alertView:(UIAlertView *)alertView clickedButt...
Class method differences in Python: bound, unbound and static
...
In Python, there is a distinction between bound and unbound methods.
Basically, a call to a member function (like method_one), a bound function
a_test.method_one()
is translated to
Test.method_one(a_test)
i.e. a call to an unbound method. Because of that, a call to...
Best practices for catching and re-throwing .NET exceptions
What are the best practices to consider when catching exceptions and re-throwing them? I want to make sure that the Exception object's InnerException and stack trace are preserved. Is there a difference between the following code blocks in the way they handle this?
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