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How do you create a Swift Date object?
... dateFromString. If you wanted to return a nil on bad parses, you would ideally use a failible initializer; but you cannot do that now (June 2015), because of a limitation in Swift 1.2, so then you're next best choice is to use a class factory method.
A more elaborate example, which addresses both ...
Installing R with Homebrew
I'm trying to install R using Homebrew. I ran these commands which are recommended elsewhere on SO:
12 Answers
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Static methods - How to call a method from another method?
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class.method should work.
class SomeClass:
@classmethod
def some_class_method(cls):
pass
@staticmethod
def some_static_method():
pass
SomeClass.some_class_method()
SomeClass.some_static_method()
sha...
Is there any overhead to declaring a variable within a loop? (C++)
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Stack space for local variables is usually allocated in function scope. So no stack pointer adjustment happens inside the loop, just assigning 4 to var. Therefore these two snippets have the same overhead.
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What is `params.require(:person).permit(:name, :age)` doing in Rails 4?
All the examples of strong parameters in Rails 4 docs use
2 Answers
2
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How to raise a ValueError?
...trates how to raise a ValueError the way you want. By-the-way, I think find_last(), find_last_index(), or something simlar would be a more descriptive name for this function. Adding to the possible confusion is the fact that Python already has a container object method named __contains__() that does...
Concept of void pointer in C programming
...ligned at 4-byte boundary to be dereferenced).
For example, reading uint16_t from void*:
/* may receive wrong value if ptr is not 2-byte aligned */
uint16_t value = *(uint16_t*)ptr;
/* portable way of reading a little-endian value */
uint16_t value = *(uint8_t*)ptr
| ((*((uint8_t*)...
Create directory if it does not exist
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What will -Force actually do? The documentation says "Forces this cmdlet to create an item that writes over an existing read-only item". Will it delete an existing folder? It should be clear in this answer.
– Peter Mortensen...
How to save a PNG image server-side, from a base64 data string
...plode(';', $data);
list(, $data) = explode(',', $data);
$data = base64_decode($data);
file_put_contents('/tmp/image.png', $data);
And as a one-liner:
$data = base64_decode(preg_replace('#^data:image/\w+;base64,#i', '', $data));
An efficient method for extracting, decoding, and checking for e...
How can I change my Cygwin home folder after installation?
I just installed Cygwin, and it looks like the home directory in the bash prompt is on my Z: drive. That's not where I want it.
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