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How to convert Nonetype to int or string?
I've got an Nonetype value x , it's generally a number, but could be None . I want to divide it by a number, but Python raises:
...
boundingRectWithSize for NSAttributedString returning wrong size
...ng to get the rect for an attributed string, but the boundingRectWithSize call is not respecting the size I pass in and is returning a rect with a single line height as opposed to a large height (it is a long string). I have experimented by passing in a very large value for the height and also 0 as ...
What does default(object); do in C#?
... value
For Nullable<T> it returns the empty (pseudo-null) value (actually, this is a re-statement of the first bullet, but it is worth making it explicit)
The biggest use of default(T) is in generics, and things like the Try... pattern:
bool TryGetValue(out T value) {
if(NoDataIsAvailab...
How can I find the method that called the current method?
When logging in C#, how can I learn the name of the method that called the current method? I know all about System.Reflection.MethodBase.GetCurrentMethod() , but I want to go one step beneath this in the stack trace. I've considered parsing the stack trace, but I am hoping to find a cleaner more ex...
Ordering by specific field value first
...
There's also the MySQL FIELD function.
If you want complete sorting for all possible values:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core", "board", "other")
If you only care that "core" is first and the other values don't matter:
SELECT id, name, priority
FROM mytable
OR...
How to easily truncate an array with JavaScript?
Linq has a convenient operator method called Take() to return a given number of elements in anything that implements IEnumerable . Is there anything similar in jQuery for working with arrays?
...
Where in memory are my variables stored in C?
...declared in functions), variables (in main function), pointers, and dynamically allocated space (using malloc and calloc) get stored in memory?
...
How to convert date to timestamp?
...(YYYY-MM-DD), which is guaranteed to be understood by Date(), and is, generally speaking, the most interoperable format for date strings.
– Walter Tross
Dec 4 '14 at 13:54
...
In absence of preprocessor macros, is there a way to define practical scheme specific flags at proje
... The simplest example is the DEBUG=1 macro that is defined by default for all Xcode projects in the default scheme for the Run build. One could query #ifdef DEBUG ... and make decisions in the code accordingly, even compiling out non-necessary code.
...
Quicksort vs heapsort
... The most direct competitor of
quicksort is heapsort. Heapsort is
typically somewhat slower than
quicksort, but the worst-case running
time is always Θ(nlogn). Quicksort is
usually faster, though there remains
the chance of worst case performance
except in the introsort variant, which...