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Align image in center and middle within div
...00%; height:100%">
<img src="http://www.garcard.com/images/garcard_symbol.png">
</div>
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Rails: How does the respond_to block work?
...html
The Responder does NOT contain a method for .html or .json, but we call these methods anyways! This part threw me for a loop.
Ruby has a feature called method_missing. If you call a method that doesn't exist (like json or html), Ruby calls the method_missing method instead.
http://ruby-meta...
What happens if you static_cast invalid value to enum class?
...ue is specified(*), and no Undefined Behaviour (UB) is involved. More generally, as you cast from the underlying type to the enumeration type, no value in data[0] can lead to UB for the static_cast.
After CWG 1766 (C++17)
See CWG defect 1766.
The [expr.static.cast]p10 paragraph has been strengthene...
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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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*)...
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
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