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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 ...
Difference between '..' (double-dot) and '…' (triple-dot) in range generation?
...
The API docs now describe this behaviour:
Ranges constructed using .. run from the beginning to the end inclusively. Those created using ... exclude the end value.
-- http://ruby-doc.org/core-2.1.3/Range.html
In other words:
2....
Custom sort function in ng-repeat
...so a function. From the orderBy documentation: https://docs.angularjs.org/api/ng/filter/orderBy):
function: Getter function. The result of this function will be sorted
using the <, =, > operator.
So, you could write your own function. For example, if you would like to compare cards ba...
How to check if a json key exists?
...ontains a specific key.
Example
JSONObject JsonObj = new JSONObject(Your_API_STRING); //JSONObject is an unordered collection of name/value pairs
if (JsonObj.has("address")) {
//Checking address Key Present or not
String get_address = JsonObj .getString("address"); // Present Key
}
else ...
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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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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Is there any overhead to declaring a variable within a loop? (C++)
...
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.
...
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...
Static methods - How to call a method from another method?
...
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...
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*)...